a(n) = (n^3 + n^2)*9^n.A129009a(n) = (n^3 + n^2)*9^n.Terms a(0) =18a(1) =972a(2) =26244a(3) =524880a(4) =8857350a(5) =133923132a(6) =1874923848a(7) =24794911296a(8) =313810596090External referencesoeis: A129009