A class function (or virtual character of a symmetric group S_n) is a function that is constant on the conjugacy classes of S_n. Class functions for S_n are in one to one correspondence with symmetric functions of degree n. The class functions corresponding to actual representations of S_n are called characters.
The character of the standard representation of S_3 is
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The character of the sign representation of S_5 is
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We can go back and forth between class functions and symmetric functions.
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We can add, subtract, multiply, scale class functions:
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The object ClassFunction is a type, with ancestor classes HashTable < Thing.