%I #8 May 30 2023 12:02:49
%S 23,35,52,78,117,176,264,396,594,891,1336,2004,3006,4509,6764,10146,
%T 15219,22828,34242,51363,77045,115567,173351,260026,390039,585059,
%U 877588,1316382,1974573,2961860,4442790,6664185,9996277,14994416
%N a(n) = 23 + floor( 1 + Sum_{j=1..n-1} a(j)/2 ).
%H Harvey P. Dale, <a href="/A120147/b120147.txt">Table of n, a(n) for n = 1..1000</a>
%t 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 *)
%o (SageMath)
%o @CachedFunction
%o def A120147(n): return 23 + (1 + sum(A120147(k) for k in range(1,n)))//2
%o [A120147(n) for n in range(1, 61)] # _G. C. Greubel_, May 30 2023
%Y Cf. A072493, A073941, A112088.
%K nonn
%O 1,1
%A _Graeme McRae_, Jun 10 2006