a(n) = Fibonacci(5*n+1).

Terms

a(0) =1a(1) =8a(2) =89a(3) =987a(4) =10946a(5) =121393a(6) =1346269a(7) =14930352a(8) =165580141a(9) =1836311903a(10) =20365011074a(11) =225851433717