kernelopts(opaquemodules=false):
RD := Algebraic:-RecursiveDensePolynomials:
p := 2^25-855: #p := 2^62-923;
m1 := z^2+z+1:
m2 := y^4-y*z-2:
m3 := x^2-x*y-4:
m4 := w^2-3*w*x-y:
R := ( [u,w,x,y,z], [m4,m3,m2,m1], p ):
g := RD:-rpoly( u+2*w*z+5*x+4*y*z+3, R ):
aa := RD:-rpoly( u+w*y+6*x+7*y*z+8, R ):
bb := RD:-rpoly( u+w*x+9*w*z+2*y+2, R ):
n := 3: # 3, 4, 7, 15, 31, 61, 127
a := RD:-mulrpoly(g,RD:-powrpoly(aa,n)):
b := RD:-mulrpoly(g,RD:-powrpoly(bb,n)):
CodeTools[Usage]( to 100 do h := RD:-gcdrpoly(a,b) od ):
RD:-rpoly(h); # check