This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A114887 #24 Feb 16 2025 08:33:00 %S A114887 120,672,32760,2178540,1379454720,14182439040,518666803200, %T A114887 30823866178560,71065075104190073088,154345556085770649600, %U A114887 9186050031556349952000,680489641226538823680000 %N A114887 Multiperfect numbers sigma(n) = k*n, which are divisible by the sum of their prime factors without repetition. %C A114887 From a list of about 5000 multiperfect numbers, 38 numbers were found with the property, all having k <= 9, the largest was the only one having k=9. A091443 uses sopfr with repetition. %C A114887 Conjecture: the sequence is finite. %H A114887 Sven Simon, <a href="/A114887/b114887.txt">Table of n, a(n) for n = 1..38</a> [Conjectured to be complete] %H A114887 Achim Flammenkamp, <a href="http://wwwhomes.uni-bielefeld.de/achim/mpn.html">The Multiply Perfect Numbers Page</a> (See here for the latest information about the search) %H A114887 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/MultiperfectNumber.html">Multiperfect numbers</a> %e A114887 a(0) = 120 = 2^3*3*5, sopf(120) = 2+3+5 = 10. %Y A114887 Cf. A091443. %Y A114887 Intersection of A007691 and A089352. - _Michel Marcus_, Oct 08 2017 %K A114887 nonn %O A114887 1,1 %A A114887 _Sven Simon_, Feb 19 2006