• 한국수학사학회지
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• 제18권1호
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• pp.75-84
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• 2005

본 논문은 군표현에 관한 역사적 배경을 알아보고, 유한군의 기약지표에 대한 어떤 조건하에서 그 군이 자명하지 않는 아벨 정규부분군을 가짐에 대한 성질들과 기약지표들의 적에 대한 성질을 증명한다.

• 한국수학사학회지
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• 제13권2호
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• pp.151-160
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• 2000

In this paper we prove that for all irreducible complex characters of a finite group, there exist F-representations and a finite degree field extension F ⊇ Q, where Q is the rational number field.

• 대한수학회논문집
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• 제18권2호
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• pp.215-223
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• 2003

Parks [7] showed that there is an one to one correspondence between good pairs of subgroups in G and irreducible monomial characters of G. This provides a useful criterion for a group to be monomial. In this paper, we study relative monomial groups by defining triples in G, and find relationships between the triples and irreducible relative monomial characters.

• Journal of applied mathematics & informatics
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• 제4권1호
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• pp.193-210
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• 1997

In this paper we find the irreducible complex characters of the automorphism group of the general linear group of degree 7 over a field with two elements. It is shown that this group has 114 irreducible complex characters.

• 한국수학사학회지
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• 제15권2호
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• pp.169-174
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• 2002

In this paper we prove that tile property of product irreducible characters is, if $\Phi$$\in$$\textit{Irr(H)}$ and $\Theta$$\in$$\textit{Irr(K)}$ are faithful, then $\Phi$$\times\theta$ is faithful if and only if │$\textit{Z(H)}$│ and │$\textit{Z(K)}$│ are relative primes where G=$\textit{H}\times\textit{K}$.

• 대한수학회지
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• 제26권2호
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• pp.291-300
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• 1989

• 대한수학회논문집
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• 제34권1호
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• pp.137-143
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• 2019

In this paper, we show that $A_4$ is the only finite group with exactly two conjugacy classes of the same size having some non-real linear characters.

• 대한수학회보
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• 제60권6호
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• pp.1497-1522
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• 2023

In this paper we compute the Bredon homology of wallpaper groups with respect to the family of finite groups and with coefficients in the complex representation ring. We provide explicit bases of the homology groups in terms of irreducible characters of the stabilizers.

• 대한수학회지
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• 제57권5호
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• pp.1187-1237
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• 2020

Simply reducible groups are important in physics and chemistry, which contain some of the important groups in condensed matter physics and crystal symmetry. By studying the group structures and irreducible representations, we find some new examples of simply reducible groups, namely, dihedral groups, some point groups, some dicyclic groups, generalized quaternion groups, Heisenberg groups over prime field of characteristic 2, some Clifford groups, and some Coxeter groups. We give the precise decompositions of product of irreducible characters of dihedral groups, Heisenberg groups, and some Coxeter groups, giving the Clebsch-Gordan coefficients for these groups. To verify some of our results, we use the computer algebra systems GAP and SAGE to construct and get the character tables of some examples.

• 대한수학회지
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• 제34권2호
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• pp.453-467
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• 1997

A transitive permutation representation of a group G is said to be multiplicity-free if all of its irreducible constituents are distinct. The character corresponding to the action is called the permutation character, given by $(1_H)^G$, where H is the stabilizer of a point. Multiplicity-free permutation characters are of interest in the study of centralizer algebras and distance-transitive graphs, and all finite simple groups are known to have such characters. In this article, we extend to the alternating groups the result of J. Saxl who determined the multiplicity-free permutation representations of the symmetric groups. We classify all subgroups H for which $(1_H)^An, n > 18$, is multiplicity-free.