1. Introduction
Everywhere in this article, let
X represent an associative ring with the center denoted by
. A ring is classified as a prime ring if for any elements
, the condition
implies that
or
, and semiprime if for any
,
implies that
. Equivalently, a ring
X is classified as prime if for any two nonzero ideals
in
X, then
, and semiprime if for any ideal
M in
X such that
, then
. Extending this notion, a proper ideal
L is said to be prime if and only if for some
,
, then either
or
. Equivalently, a proper ideal
L in
X is classified as prime if
for some ideals
in
X, then either
or
. Furthermore, a ring is termed an integral domain if it is a commutative ring with unity and is devoid of zero divisors. For more details and examples of the previous concepts, please refer to the relevant literature. A Lie product is defined for some
as
. A ring
X is said to be commutative if and only if the Lie product equals zero. A Jordan product is defined for some
as
. The characteristic of a ring
X is said to be different from 2 if for some
,
, then
, usually symbolized by
. In the case of
, we can notice that the Jordan product
. Since
, the last relation implies that
for all
. For all
, the following identities are valid and will be utilized implicitly throughout the current paper to aid in the proofs of our results:
A standard derivation
is an additive mapping satisfying the condition
for every
. For a fixed
, a map
defined by
for all
is a derivation on
X called an inner derivation induced by
r. A generalized derivation
associated with a standard derivation
is defined as an additive mapping from a ring
X to itself, satisfying
for every
. In fact, the concept of derivations plays a crucial role, alongside other concepts such as fractional derivatives (including
q-derivatives), in the generalization of theory of classical differentiation and its applications in various mathematical and physical contexts. For more details, please see [
1,
2].
By imposing two endomorphisms
and
on
X, a generalization of the concept of a derivation has been introduced as an
-derivation. This is an additive mapping
of
X that fulfills the equation
for all
. Additionally, an additive mapping
is known as a generalized
-derivation if there exists an
-derivation
such that
for all
. It is important to note that if
, where
is an identity mapping defined as
for all
, then the notion of a generalized derivation is obtained. This implies that the notion of a generalized
-derivation encompasses the notion of a generalized derivation. In recent decades, numerous researchers have examined the behavior of prime and semi-prime rings using certain equations that include appropriate additive mappings. These mappings can operate on the entire ring or on suitable subsets of it. For further exploration, examples and counterexamples can be found in [
3,
4,
5], and their bibliographies. Instead of solely focusing on the primeness or semi-primeness of a ring
X in previous studies, several researchers have opted to investigate a more general context by imposing a prime ideal
of an arbitrary ring
X. They then analyze the algebraic properties of the factor ring
under the impact of various types of additive mappings that satisfy multiple algebraic identities involving a prime ideal
L. For more detailed information on these findings, please refer to [
6,
7].
An
L-derivation is a generalization of the notion of a derivation, defined as a map from
X to
X that satisfies the following properties:
(
L-additive),
for all
. A generalized
L-derivation
associated with an
L-derivation
is defined as a map from
X to
X satisfying the following conditions for all
:
,
, where
L is a prime ideal of
X. It is clear that every generalized derivation is a generalized
L-derivation, but the converse is not generally valid. A counterexample can be found in [
8]. In fact, the equivalence between these two notions is achieved when
.
In their article [
9], Mohssine et al. introduced the concept of an
-
L-derivation
, where
and
are automorphisms of a near-ring
ℵ. They examined the effects of
on the behavior of a factor near-ring
when
satisfies certain algebraic identities involving an ideal
L of
ℵ. A year later, in [
8], Sandhu et al. studied the relationship between a factor ring
and certain differential identities involving an
L-derivation, a generalized
L-derivation, and an
L-left multiplier. Recently, Hummdi et al. in [
10] continued these studies with some differential identities involving a pair of generalized
L-derivations
and
associated with
L-derivations
and
ð, respectively.
In light of the above, the study of the properties of algebraic structures of rings, whether they are prime, semi-prime, or factor rings, has become increasingly important through various generalized forms of derivations. The question that arises is the following: Can we extend the scope of these derivations by defining one that encompasses previous definitions, thereby automatically including previous studies? The answer to this question will be addressed in this article.
Encouraged by the notions of generalized L-derivations and -L-derivations, this article introduces a novel additive mapping called a generalized -L-derivation associated with a -L-derivation , where and are endomorphisms of a ring X. We then relate a ring X to a prime ideal L by imposing certain algebraic identities that ensure a generalized -L-derivation , and investigate the relationship between the algebraic structure of a factor ring . Furthermore, we explore various outcomes that arise under specific constraints. In addition, we provide a list of illustrative examples to demonstrate the necessity of our hypothesis in various theorems.
2. Preliminary Results
Since every ring is a near-ring, we can easily define the following with the aid of ([
9], Definition 1):
Definition 1. Let L be a prime ideal of a ring X, and let τ and be endomorphisms of X. A mapping is said to be an -L-derivation if the following criteria are fulfilled for all :
, and .
To further explore the properties of the algebraic structure of a factor ring within the scope of our current study, we extend Definition 1 to encompass a generalized -L-derivation associated with an -L-derivation.
Definition 2. Let L be a prime ideal of a ring X, and let τ and be endomorphisms of X. A mapping is said to be a generalized -L-derivation if there exists an -L-derivation such that the following criteria are fulfilled for all :
, and .
Next, we will explore examples that illustrate the existence and comprehensiveness of the previous definition. But before we do that, let us introduce the following definition:
Definition 3. Following [11,12], let be a set with n-generator elements . This set consists of elements, i.e., . In the following, the set , where will denote the generator elements of . To define the operations of addition and multiplication on , we consider the set of elements , where , which are generated by , where . This precisely defines the additive operation on . For instance, if , then where and , so , which correspond to the ring in ([11], Example 2.1). Now, let us categorize two types of elements that generate , namely when the number of elements that generate is even or odd. We will denote them as and , respectively. The multiplication operation on for any , is defined as follows:For further clarification, the preceding operations of addition and multiplication on can be represented via the following Cayley tables (Table 1 and Table 2). The indices and h are merely subscripts used to distinguish between different elements in . Then is an algebra over the field . This algebra is a non-commutative ring (since while ) without the multiplicative identity 1. Furthermore, is not a prime and the characteristic of is 2. Also, every is a left zero divisor, and every is a two-sided zero divisor. Consequently, is not integral domain. Moreover, we can note that the center of the ring is equal to zero and is not reduced (it has non-zero nilpotent elements, for instance ).
Example 1. Let be as above, and let , where . Define and as follows:and Then it is easy to check that L is a prime ideal in and τ, σ are endomorphisms of . Clearly, Π and π are L-additive mappings of . Therefore, to prove that is a generalized -L-derivation of , it is sufficient to show that condition is satisfied in all the following cases for all , where :
- (a)
If and , then - (b)
If and , then - (c)
If and , then - (d)
If and , then
Therefore, we can conclude that Π is a generalized -L-derivation on , where π is an -L-derivation associated with Π.
The following two examples illustrate the comprehensiveness of Definition 2 for the concepts of generalized -derivation and generalized L-derivation.
Example 2. Let be a ring of polynomials with indeterminate w and integer coefficients, and let . Define the functions as follows:
, where of coefficients of .
, where of coefficients of .
, where maximum value of coefficients of .
, where minimum value of coefficients of .
It can be easily checked that L is a prime ideal of X, τ and σ are endomorphisms of X. Additionally, we can verify that Π is a generalized -L-derivation associated with an -L-derivation π. However, Π is not a generalized -derivation on X.
Example 3. Let , and let . Define the mapping byIt can be easily verified that L is a prime ideal of X, τ and σ are endomorphisms of X. Clearly, Π and π are L-additive mappings of X. Therefore, to prove that is a generalized -L-derivation of X, it is sufficient to show that the condition is satisfied as in the following; for any and in X. We haveTherefore, Π is a generalized -L-derivation associated with a -L-derivation π. Furthermore, it can be verified that Π is neither a generalized L-derivation nor a generalized -derivation. Remark 1. In light of the previous examples, we can conclude the following:
- (i)
If a prime ideal L equals zero, then a generalized -L-derivation is equivalent to a generalized -derivation. This also applies to an -L-derivation.
- (ii)
By setting in Definition 2, we directly obtain ([8], Definition 2).
Below, we present the next lemma that will be repeatedly employed to achieve our desired results. To prove it, only use arguments similar to the proof of ([
13], Lemma 3). Therefore, the proof is omitted.
Lemma 1. Let L be a prime ideal of a ring X, and let τ and be epimorphisms of X. Then, a factor ring is a commutative integral domain if and only if holds for all .
3. Main Result
In [
14], Quadri et al. established the commutativity of a prime ring
X with a characteristic other than two, which admits a generalized derivation
that fulfills any of the following identities:
or
for all
in a non-zero ideal
M of
X. Subsequently, Golbasi et al. [
15] examined the potential implications of the aforementioned results by substituting a non-zero ideal
M with a square closed Lie ideal
. In their work, Rahman et al. [
16] proved that a derivation
is
L-commuting on an ideal
M when an arbitrary ring
X admits a nonzero generalized derivation
that satisfies any of the following statements for every
:
,
,
,
,
,
, or
, where
L is a semiprime ideal of
X. In the context of a generalized
-derivation
associated with an
-derivation
, Sandhu et al. [
17] examined the relationship between
and the behavior of a prime ring
X that satisfies any of the identities
, or
for every
in a Lie ideal
. The following study aims to build upon previous results by incorporating more general identities that involve a comprehensive additive mapping
called a generalized
-
L-derivation associated with an
-
L-derivation
, where
and
are epimorphisms of an arbitrary ring
X and
L is a prime ideal of
X. To be concise, let’s denote a generalized
-
L-derivation
associated with an
-
L-derivation
as
. Next, we will investigate the connection between
and the behavior of a factor ring
.
Theorem 1. Assume that a ring X admits a generalized -L-derivation that satisfies any of the following statements for every :
, or
. Then either and , or is an integral domain.
Proof. Based on the given hypothesis, we have
If we replace
w with
in Equation (
1) and apply it, we obtain
By replacing
w with
in Equation (
2) and applying it, we get
The hypothesis that
is an epimorphism of
X implies that
The primeness of
L implies that for each
, either
or
. We define two subsets of
X:
and
. It is clear that both subsets
T and
S are additive subgroups of
X, and
. By invoking Brauer’s trick, we can deduce that either
or
. Consequently, we will analyze the following scenarios:
If , then we have for all . By setting , the last relation becomes and . Thus, we have for every . Using Lemma 1, we conclude that is an integral domain.
On the other scenario, if
, then for all
, we have
. For any
, replace
w with
in Equation (
1) and use it, we deduce that
By replacing
by
in Equation (
3) and applying it, we can conclude that
Therefore, the primeness of
L implies that either
or
. If
for any
, then
. In the case of
for any
,
is an integral domain, as shown by Lemma 1.
Now, if we consider the second basic hypothesis for all , then by using approaches analogous to those used in the proof of part , the desired conclusions are justified. □
In the preceding theorem, if we set
, we obtain an updated version of ([
10], Lemma 3) in the context of a generalized
-
L-derivation as follows:
Corollary 1. If a ring X admits a generalized -L-derivation , then if and only if either or is an integral domain.
Remark 2. Under certain restrictions on Theorem 1, the following can be verified:
If and , then X is commutative.
If , then either and , or is an integral domain.
If , then is an integral domain.
If the negative sign in the second term of Theorem 1 is changed to a positive sign, a different conclusion is reached. This is demonstrated in the following theorem:
Theorem 2. Assume that a ring X admits a generalized -L-derivation such that for every : . Then is an integral domain.
Proof. Let
for all
. Then we can easily verify that analogous techniques used to prove Theorem 1, with some slight variations, reduce Equation (
3) to
. Thus, for any
substituting
with
in the last expression and using it, we find
. However, for any
,
is not in
L because
L is a prime ideal of
X. Therefore, we have
. By using Lemma 1, we conclude that
is an integral domain. □
Remark 3. In Theorem 2, if or , then both assumptions imply that is an integral domain.
The following example illustrates the necessity of assuming that P is prime in Theorems 1 and 2:
Example 4. Let , . Define the mappings as follows:andIt is easy to verify that the ideal L is not a prime in X. This is because for any , where , we can check that but neither nor . Moreover, it can be verified that τ and σ are endomorphisms on X and is a generalized -L-derivation associated with an -L-derivation π that satisfies the identities imposed in Theorems 1 and 2 for every . However, is noncommutative, , and . This confirms the invalidity of Theorems 1 and 2 without assuming that L is prime. In the following theorem, we will use “anticommutator” instead of “commutator” in the first term of Theorem 1, and see what conclusions we can draw.
Theorem 3. Assume that a ring X admits a generalized -L-derivation :
- (i)
If for every , then either
- (1)
and , or
- (2)
is an integral domain and , or
- (3)
is an integral domain and .
- (ii)
If for every , then either
- (1)
and , or
- (2)
is an integral domain and , or
- (3)
is an integral domain and .
Proof. Based on the initial hypothesis, we have
By replacing
w with
in Equation (
4) and applying it, we obtain
In the previous equation, replacing
w by
and using it, we obtain
By putting
in the last equation, we can deduce that
and
. Therefore, we can conclude that
for all
. Since
is an epimorphism and
L is prime, we can determine that for all
, either
or
. Consequently, we will analyze the following two scenarios:
Scenario 1: If
for all
, then replacing
w by
in Equation (
4) and using it, we can infer
for all
. This can be expressed as
. Therefore, as discussed after Equation (
3), we can deduce that either
is an integral domain or
. The commutativity
along with our assumption that
facilitates Equation (
4) to
and
. Thus,
for all
. Substituting
w with
, for any
, we obtain
. But for any
,
because
has no non-zero divisors and
L is prime. According to this, we have
. Primeness of
L forces either
or
for all
. The last case implies that
.
Scenario 2: If
, then by using Lemma 1, we find
is an integral domain. This reduces Equation (
4) to
for all
. Recalling the primeness of
L, either
or
. By combining the case
with Definition 2
, we obtain
for all
. Substituting 𝚥 with
in the last statement and applying it, we conclude that
for all
. The primeness of
L together with our hypothesis that
is an epimorphism forces,
is not in
L, so we have
for all
. Applying this conclusion in Definition 2
, we deduce that
. Since
L is a prime ideal of
X, either
or
for all
. Our hypothesis that
is an epimorphism of
X, along with the fact that
, implies that for any
,
. Therefore, we can conclude that
.
Analogous to the proof of part , the required outcomes can be obtained when the assumed identity is for all . □
The following corollary can be immediately derived by taking in Theorem 3:
Corollary 2. Assume that a ring X admits a generalized L-derivation :
- (i)
If for every , then either
- (1)
and , or
- (2)
is an integral domain and , or
- (3)
is an integral domain and .
- (ii)
If for all , then either
- (1)
and , or
- (2)
is an integral domain and , or
- (3)
is an integral domain and .
Remark 4. Based on Theorem 3, the validity of the following situations can be verified:
If and , then X is commutative and .
If , then either is an integral domain of characteristic 2 or and is an integral domain.
Instead of , let’s consider in the second term of Theorem 3. We can then introduce the following proposition:
Proposition 1. Assume that a ring X admits a generalized -L-derivation that satisfies any one of the following statements for every :
- (i)
, or
- (ii)
. Then either
- (1)
and , or
- (2)
is an integral domain and , or
- (3)
is an integral domain and .
Proof. Following the same reasoning as the proof of Theorem 3, with some slight adjustments, we can easily derive conclusions , , and . Therefore, we will omit the proof. □
By changing the sign of the second term in identity of Theorem 3 and applying similar arguments as in the proof of Theorem 3 with necessary modifications, we observe that conclusion no longer holds. This is formally stated in the following theorem:
Theorem 4. Assume that a ring X admits a generalized -L-derivation . Then for all if and only if either
- (i)
is an integral domain of characteristic two, or
- (ii)
is an integral domain and .
The necessity of assuming that L is prime in Theorems 3, 4 is illustrated by the following example:
Example 5. In Example 4, we can note that the identities in Theorems 3, 4 and Proposition 1 satisfied, although is not an integral domain and or , , . This emphasize the necessity of the primeness assumptions in Theorems 3, 4, and Proposition 1.
Theorem 5. Assume that a ring X admits a generalized -L-derivation that satisfies any one of the following statements for every :
- (i)
, or
- (ii)
. Then either
- (1)
and , or
- (2)
is an integral domain and .
Remark 5. According to Theorem 5, the validity of the following statements can be verified:
If and , then X is commutative of characteristic two.
If , then either and , or is an integral domain of characteristic two.
If , then is an integral domain of characteristic two.
In the following theorem, we will explore the implications when the “commutator” vanishes in all terms of the identities in Theorem 1.
Theorem 6. Assume that a ring X admits a generalized -L-derivation that satisfies one of the following statements for every :
- (i)
, or
- (ii)
. Then either:
- (1)
and , or
- (2)
is an integral domain and .
Proof. Based on the initial hypothesis, we have
By replacing
w with
in the last equation and using similar tactics and arguments as in previous discussions, with necessary minor modifications, we can conclude that either
is an integral domain or
. To continue the proof, we will analyze the implications of these conclusions on our initial hypothesis in the following two scenarios:
Scenario 1: In the context of the commutativity
property of
, Equation (
6) can be expressed as
By replacing 𝚥 with
in the last equation and applying it, we get
for all
. Since
is an epimorphism of
X, we can infer that
. The primeness of
L implies that either
or
for all
. The latter case simplifies Equation (
7) to
. Using the primeness of
L, we can infer that either
or
for each
. However,
is not a zero divisor in
for any
. Therefore, we can conclude that either
or
.
Scenario 2: Considering
, if we replace
w with
in Equation (
6) and use it, we obtain
for all
. Based on our previous discussions, we can conclude that either
or
is an integral domain. If the latter case applies, we can simply apply the same strategies as in scenario 1 to reach the desired conclusion.
Assuming that for all , we can verify the proof by proceeding with arguments and techniques analogous to the proof of part , with some necessary modifications. □
Remark 6. Based on Theorem 6, we can verify the following assertions:
If a ring X is prime and , then X is commutative of characteristic two.
If , then either and , or is an integral domain and .
If , then is an integral domain of characteristic two.
If we use the positive sign instead of the negative sign in the second term of identity in Theorem 6 and apply similar strategies in the proof with necessary modifications, verifying the validity of the conclusion of the following theorem becomes straightforward:
Theorem 7. Assume that a ring X admits a generalized -L-derivation that satisfies the following statement for every : . Then is an integral domain of characteristic two.
Remark 7. In Theorem 7, if we assume that a ring X is prime or , then both assumptions imply that X is commutative.
The importance of assuming that the ideal P is prime in Theorems 5–7 is illustrated by the following example:
Example 6. Let , where is a Hamiltonian ring, and let . Define byandIt is easy to verify that Π is a generalized -L-derivation associated with an -L-derivation π. We can also note that the identities in Theorems 5–7 are satisfied. However, is neither commutative nor of characteristic 2, and . Since , but neither nor , then L is not prime. Therefore, the hypothesis that L is prime in Theorems 5–7 is necessary. Example 7. Taking into account the considerations in Example 4, we can verify that still satisfies the specified identities imposed in Theorems 5–7. However, upon examining the conclusions of these theorems, it is revealed that is not commutative of characteristic 2, , and . This confirms the invalidity of Theorems 5–7 without assuming that L is prime.
Theorem 8. Assume that a ring X admits a generalized -L-derivation . Then one of the following statements is true for every :
- (i)
,
- (ii)
if and only if either
- (1)
and , or
- (2)
is an integral domain and .
Proof. Based on the initial hypothesis, we have
Replacing 𝚥 with
in Equation (
8) and using it, we obtain
By replacing
with
in the last equation and using it, we get
Replacing 𝚥 by
in Equation (
10) and using it, we obtain
Since
is an epimorphism, the last equation becomes
The primeness of
L forces that
either
or
. Define the following two subsets of
X:
and
. It is evident that both subsets
T and
S are additive subgroups of
X and
. Recalling Brauer’s trick, we have either
or
. If
, then
. By setting
, the last equation becomes
and
. This yields that
. By applying Corollary 1, we obtain either
is an integral domain or
. In the case of
, we have
for all
. Since
L is prime and
is an epimorphism of
X, we can deduce
. Consequently, we will analyze the following two scenarios:
Scenario 1: Given
, this reduce Equation (
9) to
for all
. By setting
and utilizing the fact that
is an epimorphism, we can infer that
. Since
L is prime, we can deduce that either
or
for all
. In the first case, it implies that
. In the second case, we can conclude that
is an integral domain by applying Lemma 1.
Scenario 2: If
is an integral domain, then Equation (
9) becomes
. By replacing
w with
in the last equation and using it, we obtain
for all
. As
is an epimorphism and
L is prime, we can conclude that
.
By following similar arguments and techniques as used in the proof of part , we can derive the required conclusions when the imposed identity for all . □
Remark 8. In light of Theorem 8, the following observations can be verified:
If X is prime, then either X is commutative and or and .
If is a generalized L-derivation, then either and , or is an integral domain and .
If , then and is an integral domain.
Theorem 9. Assume that a ring X admits a generalized -L-derivation . Then one of the following statements is true for every :
- (i)
, or
- (ii)
if and only if either
- (1)
and , or
- (2)
and is an integral domain of characteristic two, or
- (3)
is an integral domain and .
Proof. Based on the initial hypothesis, we have
By simulating the tactics and arguments of the proof of Theorem 8 with some necessary modifications, we establish the following two scenarios:
Scenario 1: If
, then as discussed in scenario 1 of Theorem 8, we obtain either
is a commutative integral domain or
. In the second case, we have
and
, which is the desired conclusion
. In the first case, commutativity
of
with the assumption
reduces Equation (
11) to
for all
. Consequently, as discussed previously, we obtain either
or
.
Scenario 2: The commutativity
of
simplifies Equation (
11) to
and
. Therefore, we can deduce that
. Substituting
w with
in the previous expression and using it, we can conclude that
. Since
L is prime, for any
, we have
. Thus, the last relation becomes
. Substituting 𝚥 with
in the previous expression and using it, we can deduce that
for all
. Therefore, primeness of
L implies that
. Consequently, as discussed above, we can find that either
or
.
Assuming that for all , we can verify the proof by proceeding with arguments and techniques analogous to the proof of part , with some necessary modifications. □
Remark 9. As an application of Theorem 9, we can verify the validity of the following:
If a ring X is prime with a characteristic other than two and if , then and .
By setting and , then either and , or is an integral domain and .
Analogous to the proof of Theorem 9, with some necessary precautions, we can verify the following theorem:
Theorem 10. Assume that a ring X admits a generalized -L-derivation . Then one of the following statements is true for every :
- (i)
- (ii)
if and only if either
- (1)
and , or
- (2)
and is an integral domain of characteristic two.
Corollary 3. If a prime ring X admits a generalized -derivation such that , then one of the following statements is true for every :
- (i)
- (ii)
if and only if and X is commutative of characteristic equal to two.
Corollary 4. Assume a ring X such that . If X admits a generalized L-derivation , then one of the following statements is true for every :
- (i)
- (ii)
if and only if either
- (1)
and , or
- (2)
is an integral domain and .
In the following example, we will define mappings and a non-prime ideal on the ring in Definition 3. We will then prove that these mappings satisfy the conditions of Theorem 8, but the conclusion ultimately fails. Therefore, we can conclude that the primeness condition in this theorem cannot be ignored.
Example 8. Let , τ, σ and π are as in the Definition 3, and let . Define asThen using arguments similar to those used in Example 1, it can be easily verified that Π is a generalized -L-derivation associated with an -L-derivation π. Now let’s check that satisfies the identities , for all .
- (i)
We have for all . Therefore, it is sufficient to discuss the following cases:
- (a)
If and , then - (b)
If and , then - (c)
If and , then - (d)
If and , then
Therefore, in all cases the identity is satisfied for all . However, upon examining the conclusion of Theorem 8, we find that is isomorphic to X, which is not commutative and . However, L is not a prime ideal in X, since for some fixed elements m and l, we can see that , but and . This confirms that the primeness assumption of L in Theorem 8 cannot be neglected.
- (ii)
Similarly, the necessity of the primeness hypothesis of L in Theorem 8 for the identity for all can be verified.
Remark 10. If we consider X, τ, σ, and as in Example 8 and follow similar strategies as above, then it can be verified that satisfies the identities in Proposition 1, Theorems 9 and 10. However, when we examine the conclusions of Proposition 1, Theorems 9 and 10, we find that is not commutative, , ,, and . Hence, we can conclude that the primeness hypothesis of L in Proposition 1, Theorems 9 and 10 cannot be overcome.
The following remark indicates that Examples 4 and 6 remain valid in asserting that the primeness condition of L in Theorems 8–10 cannot be ignored.
Remark 11. Taking into account the considerations in Example 4 or Example 6, we can similarly verify that still satisfies the specified identities in Theorems 8–10 for every . However, the conclusions drawn from these theorems do not hold. This discrepancy arises from the fact that L is not a prime in X. Consequently, the assumption of primeness for L in Theorems 8–10 can not be disregarded.