cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A079076 Numerator of Sum_{1 0} n/k.

Original entry on oeis.org

0, 0, 3, 4, 65, 27, 203, 236, 3489, 2845, 53471, 21341, 757913, 553973, 619181, 1040164, 29169263, 16276383, 193614199, 116220883, 32925391, 10628013, 320160667, 455451475, 22987116115, 19980510667, 193553388003, 154777722503
Offset: 1

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Author

Reinhard Zumkeller, Dec 21 2002

Keywords

Crossrefs

Cf. A027611 (denominator), A049820, A024816.

Programs

  • Mathematica
    f[n_] := Block[{s = 0, d = 1}, While[d < n, If[ Mod[n, d] != 0, s = s + n/d]; d++ ]; s]; Numerator[ Table[ f[n], {n, 1, 28}]]

Formula

p divides a(p^k) for prime p and integer k>1. p divides a(p), a(2p) and a(2p^2) for prime p>2. - Alexander Adamchuk, Jul 27 2006

Extensions

Edited and extended by Robert G. Wilson v, Dec 30 2002