A298754 Numerator of sigma_3(n)/sigma_2(n).

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

Author

Robert Israel, Jan 26 2018

Keywords

• nonn
• frac

Links

• Robert Israel, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A001158, A001157, A000203, A091258, A091259, A091260 (denominator).

Programs

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 *)

PARI

a(n) = numerator(sigma(n, 3)/sigma(n, 2)); \\ Michel Marcus, Jan 27 2018