

A091194


Number of abundant numbers <= n.


4



0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 2, 2, 3, 3, 3, 3, 4, 4, 4, 4, 4, 4, 5, 5, 5, 5, 5, 5, 6, 6, 6, 6, 7, 7, 8, 8, 8, 8, 8, 8, 9, 9, 9, 9, 9, 9, 10, 10, 11, 11, 11, 11, 12, 12, 12, 12, 12, 12, 13, 13, 13, 13, 14, 14, 15, 15, 15, 15, 15, 15, 16, 16, 17, 17, 17, 17, 18, 18, 18
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OFFSET

1,18


LINKS



FORMULA

a(n) ~ c*n, where c = 0.247619... is the asymptotic density of the abundant numbers (A302991).  Amiram Eldar, Mar 21 2021


MATHEMATICA



PROG

(PARI) a(n) = sum(k=1, n, sigma(k)/k > 2); \\ Michel Marcus, Apr 02 2015
(Magma) [#[k:k in [1..n] DivisorSigma(1, k) gt 2*k]:n in [1..90]]; // Marius A. Burtea, Nov 06 2019


CROSSREFS



KEYWORD

nonn


AUTHOR



STATUS

approved



