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Solution to system of nonlinear equations

If you multiply the fifth character with the second, you obtain another irreducible character. The remaining missing character should be easy to determine.
Brauer Suzuki's user avatar
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Every irreducible character of $S_n$ is an integer valued function.

Personally I do not know how to do this without either Galois theory or the construction of the Specht modules. Here is the Galois theory argument, just to record it here. An element $g$ of a finite ...
Qiaochu Yuan's user avatar
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Every irreducible character of $S_n$ is an integer valued function.

I think the following can be a simple argument: one can prove that, for $G$ a finite group and $V$ a representation of $G$, $$ \chi_{V^*}(g)=\overline{\chi_V}(g)=\chi_V\left(g^{-1}\right) \quad \...
Dario Antolini's user avatar
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Why do characters fail to characterize non-abelian LCH-groups?

The short answer is that if $G$ is a group and $A$ an abelian group (like $\mathbb T$), then every group homomorphism $\phi\colon G\to A$ factors through the abelianization $G/[G,G]$. Here $[G,G]$ is ...
MaoWao's user avatar
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