

A259694


a(n) = Sum(k^6*sigma(k)*sigma(nk),k=1..n1).


1



0, 1, 195, 3496, 38195, 192780, 977386, 3216320, 9860049, 27321870, 65803045, 144005856, 308944925, 635774072, 1112550390, 2153146880, 3618341556, 6391671525, 9949570455, 16725562160, 24691972080, 40979569092, 56807498030, 89450231040, 120404165825
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OFFSET

1,3


COMMENTS

This was formerly A001479.


LINKS

Colin Barker, Table of n, a(n) for n = 1..1000
J. Touchard, On prime numbers and perfect numbers, Scripta Math., 129 (1953), 3539. [Annotated scanned copy]


MAPLE

S:=(n, e)>add(k^e*sigma(k)*sigma(nk), k=1..n1); f:=e>[seq(S(n, e), n=1..30)]; f(6);


PROG

(PARI) a(n) = sum(k=1, n1, k^6*sigma(k)*sigma(nk)) \\ Colin Barker, Jul 16 2015


CROSSREFS

Sequence in context: A172354 A295130 A257765 * A066232 A284960 A226105
Adjacent sequences: A259691 A259692 A259693 * A259695 A259696 A259697


KEYWORD

nonn


AUTHOR

N. J. A. Sloane, Jul 03 2015


STATUS

approved



