Coefficient of x in the reduction by x^2->x+1 of the polynomial p(n,x) defined below in Comments.

Terms

a(0) =0a(1) =1a(2) =2a(3) =4a(4) =7a(5) =12a(6) =21a(7) =35a(8) =58a(9) =95a(10) =155a(11) =253a(12) =411a(13) =667a(14) =1081a(15) =1751a(16) =2836a(17) =4591a(18) =7431a(19) =12026a(20) =19461a(21) =31492a(22) =50958a(23) =82455a(24) =133418a(25) =215878a(26) =349302a(27) =565186a(28) =914494a(29) =1479686