A283821 a(n) = (1 + Sum_{j=1..K-2} a(n-j)*a(n-j-1))/a(n-K) with a(1),...,a(K)=1, where K=9.

1, 1, 1, 1, 1, 1, 1, 1, 1, 8, 15, 134, 2143, 289304, 620267775, 179446568646374, 111304924045117731444223, 19973286693341774343274474438923641617, 277890644791720860549000282813744291843989379146578350083761

Offset

1,10

Links

Seiichi Manyama, Table of n, a(n) for n = 1..24

Matthew Christopher Russell, Using experimental mathematics to conjecture and prove theorems in the theory of partitions and commutative and non-commutative recurrences, PhD Dissertation, Mathematics Department, Rutgers University, May 2016; see also.

Mathematica

a[n_]:=If[n<10, 1, (1 + Sum[a[n - j] * a[n - j - 1], {j, 7}])/a[n - 9]]; Table[a[n], {n, 1, 20}] (* Indranil Ghosh, Mar 17 2017 *)

Prog

(PARI) a(n) = if(n<10, 1, (1 + sum(j=1, 7, a(n - j) * a(n - j - 1)))/a(n - 9));
for(n=1, 20, print1(a(n), ", ")) \\ Indranil Ghosh, Mar 17 2017

Crossrefs

Sequence in context: A361710 A234534 A067686 * A145219 A002406 A212593

Adjacent sequences: A283818 A283819 A283820 * A283822 A283823 A283824

Keyword

nonn

Author

N. J. A. Sloane, Mar 17 2017

Extensions

More terms from Indranil Ghosh, Mar 17 2017

Status

approved