A081865 a(n) = sigma_7(2n-1).

1, 2188, 78126, 823544, 4785157, 19487172, 62748518, 170939688, 410338674, 893871740, 1801914272, 3404825448, 6103593751, 10465138360, 17249876310, 27512614112, 42637932336, 64340198544, 94931877134, 137293757384, 194754273882, 271818611108, 373845175782

Offset

1,2

Links

Amiram Eldar, Table of n, a(n) for n = 1..10000

Mathematica

DivisorSigma[7, Range[1, 45, 2]] (* Amiram Eldar, Aug 17 2019 *)

Prog

(PARI) a(n) = sigma(2*n-1, 7); \\ Michel Marcus, Dec 04 2013

Crossrefs

Cf. A013955.

Sequence in context: A357674 A352035 A321811 * A085442 A208549 A251316

Adjacent sequences: A081862 A081863 A081864 * A081866 A081867 A081868

Keyword

nonn

Author

Benoit Cloitre, Apr 12 2003

Extensions

Three more terms from Michel Marcus, Dec 04 2013

Status

approved