a(n) = [x^n] Product_{k>=1} 1/(1 + k*x^k)^n.

Terms

a(0) =1a(1) =-1a(2) =-1a(3) =-1a(4) =27a(5) =-76a(6) =95a(7) =-295a(8) =2035a(9) =-8119a(10) =22714a(11) =-66793a(12) =254223a(13) =-988651a(14) =3444055a(15) =-11402626a(16) =39248691a(17) =-141740051a(18) =511583207a(19) =-1798826901a(20) =6256648862a(21) =-22054706773a(22) =78889160635a(23) =-281698897727a(24) =996551999479