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A120147
a(n) = 23 + floor( 1 + Sum_{j=1..n-1} a(j)/2 ).
1
23, 35, 52, 78, 117, 176, 264, 396, 594, 891, 1336, 2004, 3006, 4509, 6764, 10146, 15219, 22828, 34242, 51363, 77045, 115567, 173351, 260026, 390039, 585059, 877588, 1316382, 1974573, 2961860, 4442790, 6664185, 9996277, 14994416
OFFSET
1,1
LINKS
MATHEMATICA
nxt[{t_, a_}]:=Module[{k=Floor[(47+t)/2]}, {t+k, k}]; NestList[nxt, {23, 23}, 40][[All, 2]] (* Harvey P. Dale, Oct 29 2020 *)
PROG
(SageMath)
@CachedFunction
def A120147(n): return 23 + (1 + sum(A120147(k) for k in range(1, n)))//2
[A120147(n) for n in range(1, 61)] # G. C. Greubel, May 30 2023
CROSSREFS
KEYWORD
nonn
AUTHOR
Graeme McRae, Jun 10 2006
STATUS
approved