Coefficient of x in the reduction of the n-th Fibonacci polynomial by x^3->x^2+3x+1.

Terms

a(0) =0a(1) =1a(2) =0a(3) =5a(4) =4a(5) =28a(6) =48a(7) =183a(8) =424a(9) =1315a(10) =3420a(11) =9864a(12) =26756a(13) =75237a(14) =207128a(15) =577345a(16) =1597624a(17) =4439764a(18) =12307388a(19) =34166643a(20) =94769936a(21) =262998791a(22) =729644824a(23) =2024614928a(24) =5617339496a(25) =15586328073a(26) =43245649904a(27) =119991232893a(28) =332929027020