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D.15.14.7 PPolyN

Procedure from library goettsche.lib (see goettsche_lib).

Usage:
PPolyN(t, q, m, n); t polynomial, q, m, n integers

Return:
polynomial in t

Purpose:
computes the Poincare polynomial of the moduli space of Kronecker modules N(q; m, n)

Note:
if m and n are not coprime, the result does not necessary make sense

Example:
 
LIB "goettsche.lib";
ring r=0, (t), ls;
// get the Poincare polynomial of N(3; 2, 3)
print( PPolyN(t, 3, 2, 3) );
==> 1+t2+3t4+3t6+3t8+t10+t12