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%I #13 Jul 30 2013 16:48:59
%S 0,1,20,5040,2363739840,25724259347628441600,
%T 23551816324573058043308233789747587210723924136427520000
%N First n-fold perfect number divided by 6, or 0 if the quotient is not an integer.
%C The first n-fold perfect numbers are A007539(n) = 1, 6, 120, 30240, 14182439040, ..., for n = 1, 2, 3, 4, 5, ...
%C The first n-fold perfect numbers divided by 120 is A227766.
%C The first n-fold perfect numbers divided by 30240 is A227767.
%C The first n-fold perfect numbers divided by 14182439040 is A227768.
%C For additional comments, references, links, and cross-refs, see A007539.
%H T. D. Noe, <a href="/A227765/b227765.txt">Table of n, a(n) for n = 1..8</a>
%H E. W. Weisstein's MathWorld, <a href="http://mathworld.wolfram.com/MultiperfectNumber.html">Multiperfect Number</a>
%H Wikipedia, <a href="http://en.wikipedia.org/wiki/Multiply_perfect_number">Multiply perfect number</a>
%F a(n) = A007539(n)/6 if 2 <= n <= 8.
%e The first 3-fold perfect number is A007539(3) = 120, so a(3) = 120/6 = 20.
%Y Cf. A007539, A227766, A227767, A227768, A227769.
%K nonn
%O 1,3
%A _Jonathan Sondow_, Jul 29 2013
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