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A298754
Numerator of sigma_3(n)/sigma_2(n).
3
1, 9, 14, 73, 63, 126, 172, 117, 757, 567, 666, 146, 1099, 1548, 882, 151, 2457, 6813, 3430, 219, 2408, 5994, 6084, 1638, 15751, 9891, 1022, 12556, 12195, 7938, 14896, 12483, 9324, 22113, 10836, 55261, 25327, 6174, 15386, 567, 34461, 21672, 39754, 16206, 6813, 54756, 51912, 2114, 39331, 47253
OFFSET
1,2
LINKS
MAPLE
seq(numer(numtheory:-sigma[3](n)/numtheory:-sigma[2](n)), n=1..100);
MATHEMATICA
a[n_] := Numerator[DivisorSigma[3, n]/DivisorSigma[2, n]]; Array[a, 100] (* Amiram Eldar, Dec 20 2024 *)
PROG
(PARI) a(n) = numerator(sigma(n, 3)/sigma(n, 2)); \\ Michel Marcus, Jan 27 2018
CROSSREFS
Cf. A001158, A001157, A000203, A091258, A091259, A091260 (denominator).
Sequence in context: A272293 A272545 A272009 * A166654 A348318 A370674
KEYWORD
nonn,frac
AUTHOR
Robert Israel, Jan 26 2018
STATUS
approved