1756816domain: NAppears in sequences4 times the Lucas number A000032(n).at n=27A156279G.f.: Product_{n>=1} (1 - Lucas(n)*x^n + (-x^2)^n) / (1 + Lucas(n)*x^n + (-x^2)^n) where Lucas(n) = A000204(n).at n=45A203850