Triangle of palindromic polynomials.

Terms

a(0) =1a(1) =1a(2) =1a(3) =1a(4) =5a(5) =1a(6) =1a(7) =16a(8) =16a(9) =1a(10) =1a(11) =43a(12) =121a(13) =43a(14) =1a(15) =1a(16) =106a(17) =666a(18) =666a(19) =106a(20) =1a(21) =1a(22) =249a(23) =3089a(24) =6649a(25) =3089a(26) =249a(27) =1a(28) =1a(29) =568