a(n) = A259109(n)*A006331(n) - A259108(n)^2.

Terms

a(0) =0a(1) =0a(2) =144a(3) =6048a(4) =85536a(5) =679536a(6) =3747744a(7) =16039296a(8) =56930688a(9) =174978144a(10) =479700144a(11) =1198248480a(12) =2770653600a(13) =6002352720a(14) =12298837824a(15) =24014605824a(16) =44957265408a(17) =81097765056a(18) =141549364944a(19) =239891292576a(20) =395928108576a(21) =637992775728