# Greetings from The On-Line Encyclopedia of Integer Sequences! http://oeis.org/ Search: id:a019423 Showing 1-1 of 1 %I A019423 #34 Sep 08 2022 08:44:44 %S A019423 1,21,31,651,889,3210,3498,3710,3882,3910,4310,4922,4982,5182,5457, %T A019423 5885,6035,6095,6307,6797,7117,7327,7597,24573,27559,71193,82110, %U A019423 90510,94981,97410,98671,99301,99510,100110,103362,104622,107778,108438,108822 %N A019423 Numbers whose sum of divisors is a fifth power. %H A019423 Marius A. Burtea, Table of n, a(n) for n = 1..3648 (terms 1..1000 from Donovan Johnson; a(1211) re-indexed and duplicate a(2311) removed by _Georg Fischer_, Mar 21 2022). %H A019423 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. %o A019423 (PARI) lista(nn) = {for (i=1, nn, s = sigma(i); if (s == 1 || ispower(s, 5), print1(i, ", ")););} \\ _Michel Marcus_, Jun 12 2013 %o A019423 (Magma) [n:n in [1..10000]| IsPower(SumOfDivisors(n),5)]; // _Marius A. Burtea_, Apr 17 2019 %Y A019423 Cf. A000203, A006532, A019422, A019424, A020477, A048257, A048258. %K A019423 nonn %O A019423 1,2 %A A019423 _David W. Wilson_ # Content is available under The OEIS End-User License Agreement: http://oeis.org/LICENSE