Expansion of Product_{k>=1} 1 / (1 - 5^(k-1)*x^k).

Terms

a(0) =1a(1) =1a(2) =6a(3) =31a(4) =181a(5) =931a(6) =5431a(7) =27931a(8) =159806a(9) =834806a(10) =4697306a(11) =24478556a(12) =137931681a(13) =717306681a(14) =3989650431a(15) =20958791056a(16) =115494337931a(17) =604881056681