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A306843 a(n) = Sum_{d|n} binomial(n,d)^3. 1
1, 9, 28, 281, 126, 11592, 344, 365465, 593434, 16095134, 1332, 921113624, 2198, 40424993884, 27175280778, 2137777203097, 4914, 121331143444050, 6860, 6310445825215406, 1572228697798262, 351047164202718608, 12168, 20174300460344963864, 149975199312626 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Seiichi Manyama, Table of n, a(n) for n = 1..1000

FORMULA

If p is prime, a(p) = A001093(p).

PROG

(PARI) {a(n) = sumdiv(n, d, binomial(n, d)^3)}

CROSSREFS

Sum_{d|n} binomial(n,d)^b: A000005 (b=0), A056045 (b=1), A174462 (b=2), this sequence (b=3).

Cf. A000172, A001093, A001158.

Sequence in context: A226976 A042501 A271185 * A277511 A041154 A024121

Adjacent sequences:  A306840 A306841 A306842 * A306844 A306845 A306846

KEYWORD

nonn

AUTHOR

Seiichi Manyama, Mar 12 2019

STATUS

approved

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Last modified May 31 20:23 EDT 2020. Contains 334748 sequences. (Running on oeis4.)