a(n) = coefficient of x^(2n) in the expansion of the modular form Product_{k>=1} (1-x^k)^n.

Terms

a(0) =1a(1) =-1a(2) =1a(3) =-7a(4) =9a(5) =9a(6) =49a(7) =-176a(8) =57a(9) =-673a(10) =2401a(11) =1143a(12) =-9063a(13) =33201a(14) =-153502a(15) =315783a(16) =-755943a(17) =2210985a(18) =-767039a(19) =1790369a(20) =-40127031a(21) =44496424a(22) =-58813391a(23) =1040502519a(24) =-1696965207a(25) =-1810005816a(26) =-4483997699a(27) =7445790947a(28) =105920054242a(29) =-134133273672