FUNCTION: heralg[coxeter_polynomial] - the characteristic polynomial of the Coxeter matrix of a quiver algebra

CALLING SEQUENCE:
coxeter_polynomial(Q)

PARAMETERS:
Q - a quiver given by a quiverdata structure

SYNOPSIS:

• The function coxeter_polynomial(Q) computes the Coxeter polynomial, i.e. the characteristic polynomial of the Coxeter matrix of the path algebra of the quiver Q.

• This function is part of the heralg package, and so can be used in the form coxeter_polynomial(..) only after performing the command with(heralg) or with(heralg, coxeter_polynomial). The function can always be accessed in the long form heralg[coxeter_polynomial](..).

EXAMPLES:

> with(heralg):

> coxeter_polynomial( [2,[[1,2,r]]] );

> Q := [ 3, [[1,2], [2,3,2]]];

> coxeter_polynomial(Q);