G.f.: Product_{n>=1} (1 - 2*x^n)^3.

Terms

a(0) =1a(1) =-6a(2) =6a(3) =22a(4) =-30a(5) =-30a(6) =-26a(7) =102a(8) =138a(9) =-94a(10) =6a(11) =-450a(12) =-214a(13) =258a(14) =462a(15) =846a(16) =234a(17) =618a(18) =-1490a(19) =-2274a(20) =-2382a(21) =554a(22) =-402a(23) =2070a(24) =8178a(25) =3018a(26) =7638a(27) =-3226a(28) =-4878a(29) =-15246