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A076233 Sigma[1, n]/n, Sigma[3, n]/n are integers. 2
1, 6, 120, 496, 672, 8128, 30240, 32760, 523776, 23569920, 33550336, 459818240, 1379454720, 1476304896, 8589869056, 31998395520, 51001180160, 66433720320 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..18.

PROG

(PARI) isok(n) = !(sigma(n) % n) && !(sigma(n, 3) % n); \\ Michel Marcus, Dec 26 2013

CROSSREFS

Cf. A007691, A046763, A055709, A076231, A076234.

Sequence in context: A227027 A001219 A224303 * A066581 A054776 A076231

Adjacent sequences:  A076230 A076231 A076232 * A076234 A076235 A076236

KEYWORD

nonn,more

AUTHOR

Labos Elemer, Oct 04 2002

STATUS

approved

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Last modified January 22 15:57 EST 2019. Contains 319364 sequences. (Running on oeis4.)