Why Should the Littlewood–richardson Rule Be True?
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چکیده
We give a proof of the Littlewood-Richardson Rule for describing tensor products of irreducible finite-dimensional representations of GLn. The core of the argument uses classical invariant theory, especially (GLn,GLm)duality. Both of the main conditions (semistandard condition, lattice permutation/Yamanouchi word condition) placed on the tableaux used to define Littlewood-Richardson coefficients have natural interpretations in the argument.
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