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A081861 (1/24)*(sigma_3(2n-1)-sigma_1(2n-1)). 1
0, 1, 5, 14, 31, 55, 91, 146, 204, 285, 400, 506, 655, 850, 1015, 1240, 1552, 1804, 2109, 2562, 2870, 3311, 3971, 4324, 4914, 5730, 6201, 6990, 8000, 8555, 9455, 10846, 11536, 12529, 14192, 14910, 16206, 18371, 19088, 20540, 22990, 23821, 25794 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

LINKS

Harvey P. Dale, Table of n, a(n) for n = 1..1000

MATHEMATICA

Table[(DivisorSigma[3, 2n-1]-DivisorSigma[1, 2n-1])/24, {n, 50}] (* Harvey P. Dale, Dec 15 2012 *)

CROSSREFS

Cf. A000203, A001158, A081863(1).

Sequence in context: A238604 A166068 A070129 * A299903 A299276 A267167

Adjacent sequences:  A081858 A081859 A081860 * A081862 A081863 A081864

KEYWORD

nonn

AUTHOR

Benoit Cloitre, Apr 11 2003

STATUS

approved

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Last modified April 18 09:06 EDT 2021. Contains 343087 sequences. (Running on oeis4.)