A022864 a(n) = [ a(n-1)/a(1) ] + [ a(n-2)/a(2) ] + ... + [ a(1)/a(n-1) ], for n >= 3.

1, 2, 2, 3, 5, 7, 10, 16, 25, 41, 65, 105, 169, 274, 443, 720, 1169, 1898, 3082, 5007, 8135, 13216, 21473, 34891, 56692, 92118, 149682, 243219, 395210, 642182, 1043490, 1695582, 2755177, 4476933, 7274641, 11820688, 19207633, 31210810

Offset

1,2

Links

Clark Kimberling, Table of n, a(n) for n = 1..1000

Formula

a(n) ~ c * d^n, where d = 1.624917080308792668777176060024247061410853634382520938693643315503399..., c = 0.303891959005299690223882625168892655788121567053552039563488551080739... . - Vaclav Kotesovec, Jun 24 2016

Mathematica

a[1] = 1; a[2] = 2; a[3] = 2;
a[n_] := a[n] = Floor[Sum[a[n - k]/a[k], {k, 1, n - 1}]];
Table[a[n], {n, 1, 100}]
(* Clark Kimberling, Jun 23 2016 *)

Crossrefs

Cf. A022863.

Sequence in context: A001083 A173696 A120412 * A316075 A322429 A039894

Adjacent sequences: A022861 A022862 A022863 * A022865 A022866 A022867

Keyword

nonn

Author

Clark Kimberling

Status

approved