A120136 a(n) = 7 + floor(Sum_{j=1..n-1} a(j) / 2).

7, 10, 15, 23, 34, 51, 77, 115, 173, 259, 389, 583, 875, 1312, 1968, 2952, 4428, 6642, 9963, 14945, 22417, 33626, 50439, 75658, 113487, 170231, 255346, 383019, 574529, 861793, 1292690, 1939035, 2908552, 4362828, 6544242, 9816363, 14724545

Offset

1,1

Links

Harvey P. Dale, Table of n, a(n) for n = 1..1000

Mathematica

nxt[{t_, a_}] := Module[{c=7+Floor[t/2]}, {t+c, c}];
NestList[nxt, {7, 7}, 40][[All, 2]] (* Harvey P. Dale, Jan 13 2017 *)

Prog

(SageMath)
@CachedFunction
def A120136(n): return 7 +sum(A120136(k) for k in range(1, n))//2
[A120136(n) for n in range(1, 60)] # G. C. Greubel, May 08 2023

Crossrefs

Cf. A073941, A072493, A112088, A120134, A120135, A120137 - A120209.

Sequence in context: A030764 A155716 A025002 * A020743 A088350 A085382

Adjacent sequences: A120133 A120134 A120135 * A120137 A120138 A120139

Keyword

nonn

Author

Graeme McRae, Jun 10 2006

Status

approved