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 A218407 #24 May 13 2023 20:00:44 %S A218407 30,140,2480,6200,40640,297600,997920,64995840,167751680,1502582400, %T A218407 42949345280,183196016640,687193456640,1447428787200,63870637017600, %U A218407 326676430080000,20797363851264000,24871926476966400,42981218625945600,404918548479244800 %N A218407 Numbers k for which sigma(k)/k - 2/5 is an integer. %C A218407 a(12) > 10^11. - _Donovan Johnson_, Oct 31 2012 %C A218407 a(14) > 10^12. - _Giovanni Resta_, Nov 04 2012 %C A218407 Note that there are no terms here with abundancy 7/5 (k=1). - _Michel Marcus_, Jun 26 2013 %Y A218407 Cf. A218406, A218408, A218427. %K A218407 nonn %O A218407 1,1 %A A218407 _Zdenek Cervenka_, Oct 28 2012 %E A218407 a(8)-a(11) from _Donovan Johnson_, Oct 31 2012 %E A218407 a(12)-a(13) from _Giovanni Resta_, Nov 04 2012 %E A218407 More terms from _Michel Marcus_, Jun 26 2013