read qrabbit: print(`The output of "Lewis" for the proposed expression in`): print(`"A q-generalization of a determinant conjectured`): print(`by Kuperberg and Propp", is:`): lprint(``): Lewis( (a+b)!*(2*n+1)!^(m+1)*TP(2*n-m)*TP(m)*TP(a)*TP(b)*TP(m+a+b)*TP(2*n-m-a-b)*TP(n-m-a-1)*TP(n-m-b-1)/a!/b!/ TP(2*n+1)/TP(a+b)/TP(n-a)/TP(n-b)/TP(m+a)/TP(m+b)/TP(2*n-2*m-a-b-1), a,b,m): print(``): y:=q^((m+1)*(a-b)*(a-b+1)/2): print(`the q-analogues being`): gu1:=(1-q^(2*n-m-a-b+1))*(1-q^(m+a+b+1))/(1-q^(2*n-m+2))/(1-q^m): gu1:=gu1*simplify(subs(m=m-1,y)*subs({m=m-1,a=a+1,b=b+1},y)/y/subs({m=m-2,a=a+1,b=b+1},y)): print(gu1): print(`and`): gu2:=(1-q^(a+b+1))*(1-q^(2*n-2*m-a-b+1))/(1-q^(2*n-m+2))/(1-q^m): gu2:=gu2*simplify(subs(m=m-1,a=a+1,y)*subs({m=m-1,b=b+1},y)/y/subs({m=m-2,a=a+1,b=b+1},y)): print(gu2): print(``): print(`the difference is:`): gu3:=simplify(gu1-gu2): print(gu3): print(`this reduces to `): gu3:=numer(expand(gu3))/expand(denom(gu3)): print(gu3):