E.g.f.: Product_{k>=1} (1 + x^k)^(cos(x)/k).

Terms

a(0) =1a(1) =1a(2) =1a(3) =2a(4) =-1a(5) =-6a(6) =109a(7) =1154a(8) =-2507a(9) =18392a(10) =829181a(11) =6383244a(12) =-2209703a(13) =-107812394a(14) =4571476337a(15) =317794760230