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%I #10 May 03 2021 02:13:25
%S 1,2,3,3,4,5,6,7,7,7,8,9,11,12,13,13,14,15,17,18,19,19,20,21,22,23,23,
%T 23,24,25,27,29,30,31,31,31,32,33,34,35,37,38,40,42,43,43,44,45,46,47,
%U 47,47,48,49,50,51,52,53,54,55,57,59,60,61,61,61,62,63,64,65,67,68,70,72,73,73,73,73,74,75,76,77,79
%N Partial sums of A335294.
%H Seiichi Manyama, <a href="/A334714/b334714.txt">Table of n, a(n) for n = 1..10000</a>
%H Altug Alkan, Andrew R. Booker, and Florian Luca, <a href="https://arxiv.org/abs/2006.08013">On a recursively defined sequence involving the prime counting function</a>, arXiv:2006.08013 [math.NT], 2020.
%t f[1] = 1; f[n_] := f[n] = PrimePi[n] - PrimePi[Sum[f[k], {k, 1, n - 1}]]; Accumulate @ Array[f, 100] (* _Amiram Eldar_, May 03 2021 *)
%Y Cf. A335294.
%K nonn
%O 1,2
%A _N. J. A. Sloane_, Jun 16 2020