Expansion of Product_{k>=1} (1 + 2*x^k)/(1 - x^k).

Terms

a(0) =1a(1) =3a(2) =6a(3) =15a(4) =27a(5) =51a(6) =93a(7) =159a(8) =264a(9) =432a(10) =696a(11) =1086a(12) =1683a(13) =2553a(14) =3837a(15) =5700a(16) =8367a(17) =12147a(18) =17505a(19) =24972a(20) =35361a(21) =49728a(22) =69402a(23) =96243a(24) =132657a(25) =181782a(26) =247692a(27) =335838a(28) =453042a(29) =608289