Expansion of e.g.f: (1+x)*cos(x).

Terms

a(0) =1a(1) =1a(2) =-1a(3) =-3a(4) =1a(5) =5a(6) =-1a(7) =-7a(8) =1a(9) =9a(10) =-1a(11) =-11a(12) =1a(13) =13a(14) =-1a(15) =-15a(16) =1a(17) =17a(18) =-1a(19) =-19a(20) =1a(21) =21a(22) =-1a(23) =-23a(24) =1a(25) =25a(26) =-1a(27) =-27a(28) =1a(29) =29