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 A214266 #11 Jul 10 2012 10:19:12 %S A214266 1,103654150315463023813006470,207308300630926047626012940, %T A214266 414616601261852095252025880,518270751577315119065032350, %U A214266 829233202523704190504051760,982794906694760522078876160,1036541503154630238130064700 %N A214266 Numbers n such that n, phi(n) and sigma(n) have same set of prime factors. %H A214266 Michel Marcus, <a href="/A214266/b214266.txt">Table of n, a(n) for n = 1..100</a> %H A214266 Prime Puzzles, <a href="http://www.primepuzzles.net/puzzles/puzz_451.htm">Puzzle 451</a> %e A214266 For n = 207308300630926047626012940 = 2^2*3^4*5*7*11*13^3*17^3*29^2*31^3*37^2*67^2 %e A214266 phi(n) = 2^18*3^9*5^2*7*11*13^2*17^2*29*31^2*37*67 and %e A214266 sigma(n) = 2^16*3^6*5^2*7^5*11^2*13^2*17*29*31*37*67^2 %e A214266 have the same prime factors. %Y A214266 Cf. A027598, A055744, A081377. %K A214266 nonn,fini %O A214266 1,2 %A A214266 _Michel Marcus_, Jul 09 2012