1-sequence of reduction of binomial coefficient sequence B(n,4)=A000332 by x^2 -> x+1.

Terms

a(0) =0a(1) =5a(2) =20a(3) =90a(4) =300a(5) =930a(6) =2610a(7) =6900a(8) =17295a(9) =41605a(10) =96660a(11) =218145a(12) =480225a(13) =1034765a(14) =2188385a(15) =4552745a(16) =9334760a(17) =18892805a(18) =37794765a(19) =74817520a(20) =146702410a(21) =285169310a(22) =549948760a(23) =1052879110a(24) =2002263910a(25) =3784182685a(26) =7110957850a(27) =13291250220