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7.5.3.0. PBW_eqDeg
Procedure from library central.lib (see central_lib).

Usage:
PBW_eqDeg(Deg); Deg int

Purpose:
Compute PBW elements of a given degree.

Return:
ideal consisting of found elements.

Note:
Unit is omitted. Weights are ignored!

Example:
 
LIB "central.lib";
ring AA = 0,(e,f,h),dp;
matrix D[3][3]=0;
D[1,2]=-h;  D[1,3]=2*e;  D[2,3]=-2*f;
def A = nc_algebra(1,D); setring A; // this algebra is U(sl_2)
// PBW Basis of A_2 \ A_1 - monomials of degree == 2:
PBW_eqDeg( 2 );
==> _[1]=h2
==> _[2]=fh
==> _[3]=f2
==> _[4]=eh
==> _[5]=ef
==> _[6]=e2