Constant term of the reduction by x^2 -> x+1 of the polynomial p(n,x) defined at Comments.

Terms

a(0) =1a(1) =-1a(2) =3a(3) =7a(4) =17a(5) =33a(6) =61a(7) =107a(8) =183a(9) =307a(10) =509a(11) =837a(12) =1369a(13) =2231a(14) =3627a(15) =5887a(16) =9545a(17) =15465a(18) =25045a(19) =40547a(20) =65631a(21) =106219a(22) =171893a(23) =278157a(24) =450097a(25) =728303a(26) =1178451a(27) =1906807a(28) =3085313a(29) =4992177