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A307741
Sum of divisors of the multiply-perfect numbers.
3
1, 12, 56, 360, 992, 2016, 16256, 120960, 131040, 1571328, 8714160, 94279680, 67100672, 182131200, 571963392, 1379454720, 5517818880, 4428914688, 17179738112, 70912195200, 159991977600, 175445913600, 153003540480, 265734881280, 274877382656, 612014161920
OFFSET
1,2
COMMENTS
When sorted, this is A081756. - N. J. A. Sloane, May 03 2019
LINKS
FORMULA
a(n) = sigma(A007691(n)) = A000203(A007691(n)).
a(n) = A007691(n) * A054030(n).
EXAMPLE
For n = 3; a(3) = sigma(A007691(3)) = sigma(28) = 56.
PROG
(Magma) [SumOfDivisors(n): n in [1..1000000] | IsIntegral(SumOfDivisors(n)/n)]
(PARI) lista(nn) = {for (n=1, nn, my(s=sigma(n)); if (! (s % n), print1(s, ", ")); ); } \\ Michel Marcus, Apr 26 2019
CROSSREFS
See also A081756.
Sequence in context: A068414 A199316 A081756 * A027147 A095724 A225880
KEYWORD
nonn
AUTHOR
Jaroslav Krizek, Apr 26 2019
STATUS
approved