FUNCTION: Perm2Sign - return the signature of a permutation

CALLING SEQUENCE:

Perm2Sign(perm)

SG[Perm2Sign](perm)

PARAMETERS:

perm = any list denoting a permutation

SYNOPSIS:

• The Perm2Sign function calculates the signature of a permutation. This value is equal to (-1)^(the length of the permutation).

• Whenever there is a conflict between the function name Perm2Sign and another name used in the same session, use the long form SG['Perm2Sign'].

EXAMPLES:

> with(SG):
> Perm2Sign([1,4,2,3]);
 
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