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

Terms

a(0) =1a(1) =2a(2) =6a(3) =12a(4) =23a(5) =41a(6) =71a(7) =120a(8) =200a(9) =330a(10) =541a(11) =883a(12) =1437a(13) =2334a(14) =3786a(15) =6136a(16) =9939a(17) =16093a(18) =26051a(19) =42164a(20) =68236a(21) =110422a(22) =178681a(23) =289127a(24) =467833a(25) =756986a(26) =1224846a(27) =1981860a(28) =3206735a(29) =5188625