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A013941
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a(n) = Sum_{k = 1..n} floor(n/prime(k)^3).
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1
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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, 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, 10, 10, 10, 10, 10, 11, 11, 11, 11
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refs;
listen;
history;
text;
internal format)
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OFFSET
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1,16
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LINKS
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Table of n, a(n) for n=1..75.
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FORMULA
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G.f.: (1/(1 - x))*Sum_{k>=1} x^(prime(k)^3)/(1 - x^(prime(k)^3)). - Ilya Gutkovskiy, Feb 11 2017
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MAPLE
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A013941:=n->add(floor(n/ithprime(k)^3), k=1..n): seq(A013941(n), n=1..150); # Wesley Ivan Hurt, Jan 29 2017
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MATHEMATICA
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Table[Floor[Sum[n/Prime[k]^3, {k, n}]], {n, 75}] (* Alonso del Arte, Jan 29 2017 *)
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PROG
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(PARI) a(n) = sum(k = 1, n, n\prime(k)^3); \\ Michel Marcus, Aug 24 2013
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CROSSREFS
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Cf. A013940.
Partial sums of A295659.
Sequence in context: A179528 A105390 A347941 * A061798 A345206 A318585
Adjacent sequences: A013938 A013939 A013940 * A013942 A013943 A013944
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KEYWORD
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nonn,easy
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AUTHOR
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N. J. A. Sloane, Henri Lifchitz
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STATUS
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approved
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