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A019423
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Numbers n such that sum of divisors of n is a fifth power.
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12
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1, 21, 31, 651, 889, 3210, 3498, 3710, 3882, 3910, 4310, 4922, 4982, 5182, 5457, 5885, 6035, 6095, 6307, 6797, 7117, 7327, 7597, 24573, 27559, 71193, 82110, 90510, 94981, 97410, 98671, 99301, 99510, 100110, 103362, 104622, 107778, 108438, 108822
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history;
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OFFSET
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1,2
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LINKS
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Marius A. Burtea, Table of n, a(n) for n = 1..3650 (terms 1..1000 from Donovan Johnson).
Frits Beukers, Florian Luca and Frans Oort, Power Values of Divisor Sums, The American Mathematical Monthly, Vol. 119, No. 5 (May 2012), pp. 373-380.
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PROG
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(PARI) lista(nn) = {for (i=1, nn, s = sigma(i); if (s == 1 || ispower(s, 5), print1(i, ", ")); ); } \\ Michel Marcus, Jun 12 2013
(MAGMA) [n:n in [1..10000]| IsPower(SumOfDivisors(n), 5)]; // Marius A. Burtea, Apr 17 2019
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CROSSREFS
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Cf. A000203, A006532, A019422, A019424, A020477, A048257, A048258.
Sequence in context: A068657 A068671 A166668 * A002639 A054282 A095994
Adjacent sequences: A019420 A019421 A019422 * A019424 A019425 A019426
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KEYWORD
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nonn
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AUTHOR
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David W. Wilson
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STATUS
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approved
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