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%I #23 Jun 26 2022 22:45:58
%S 0,0,0,0,0,0,0,1,1,1,1,1,1,1,1,2,2,2,2,2,2,2,2,3,3,3,4,4,4,4,4,5,5,5,
%T 5,5,5,5,5,6,6,6,6,6,6,6,6,7,7,7,7,7,7,8,8,9,9,9,9,9,9,9,9,10,10,10,
%U 10,10,10,10,10,11,11,11,11
%N a(n) = Sum_{k = 1..n} floor(n/prime(k)^3).
%F G.f.: (1/(1 - x))*Sum_{k>=1} x^(prime(k)^3)/(1 - x^(prime(k)^3)). - _Ilya Gutkovskiy_, Feb 11 2017
%p A013941:=n->add(floor(n/ithprime(k)^3), k=1..n): seq(A013941(n), n=1..150); # _Wesley Ivan Hurt_, Jan 29 2017
%t Table[Floor[Sum[n/Prime[k]^3, {k, n}]], {n, 75}] (* _Alonso del Arte_, Jan 29 2017 *)
%o (PARI) a(n) = sum(k = 1, n, n\prime(k)^3); \\ _Michel Marcus_, Aug 24 2013
%Y Cf. A013940.
%Y Partial sums of A295659.
%K nonn,easy
%O 1,16
%A _N. J. A. Sloane_, _Henri Lifchitz_
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