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A120143
a(n) = 17 + floor( (1 + Sum_{j=0..n-1} a(j))/2 ).
3
17, 26, 39, 58, 87, 131, 196, 294, 441, 662, 993, 1489, 2234, 3351, 5026, 7539, 11309, 16963, 25445, 38167, 57251, 85876, 128814, 193221, 289832, 434748, 652122, 978183, 1467274, 2200911, 3301367, 4952050, 7428075, 11142113, 16713169
OFFSET
1,1
LINKS
MATHEMATICA
nxt[{t_, a_}]:=Module[{c=17+Floor[(1+t)/2]}, {t+c, c}]; NestList[nxt, {17, 17}, 60][[All, 2]] (* Harvey P. Dale, Dec 25 2020 *)
PROG
(SageMath)
@CachedFunction
def A120143(n): return 17 + (1 +sum(A120143(k) for k in range(1, n)))//2
[A120143(n) for n in range(1, 60)] # G. C. Greubel, May 11 2023
KEYWORD
nonn
AUTHOR
Graeme McRae, Jun 10 2006
STATUS
approved