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SchurRing -- the class of all Schur rings

Description

A Schur ring is the representation ring for the general linear group of n by n matrices, and one can be constructed with schurRing.
i1 : R = schurRing(s, 4)

o1 = R

o1 : SchurRing
The element corresponding to the Young diagram {3,2,1} is obtained as follows.
i2 : s_{3,2,1}

o2 = s
      3,2,1

o2 : R
The dimension of the underlying virtual representation can be obtained with dim.
i3 : dim s_{3,2,1}

o3 = 64
Multiplication in the ring comes from tensor product of representations.
i4 : s_{3,2,1} * s_{1,1}

o4 = s      + s      + s        + s      + s        + s
      4,3,1    4,2,2    4,2,1,1    3,3,2    3,3,1,1    3,2,2,1

o4 : R

See also

Functions and methods returning a Schur ring :

Methods that use a Schur ring :

For the programmer

The object SchurRing is a type, with ancestor classes EngineRing < Ring < Type < MutableHashTable < HashTable < Thing.