O.g.f.: exp( Sum_{n>=1} -(sigma(2*n^3) - sigma(n^3)) * (-x)^n/n ).

Terms

a(0) =1a(1) =2a(2) =-6a(3) =12a(4) =38a(5) =-108a(6) =148a(7) =168a(8) =-922a(9) =2294a(10) =-2656a(11) =-1732a(12) =17908a(13) =-44516a(14) =60896a(15) =-6936a(16) =-206474a(17) =650848a(18) =-1181394a(19) =1146324a(20) =865832a(21) =-6609592a(22) =16632596a(23) =-26643544a(24) =22498916a(25) =23275482a(26) =-144152248a(27) =349896736a(28) =-563311472a(29) =532552508