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 A072896 #9 Jul 25 2017 02:18:40 %S A072896 1,4150,4151,54748,58618,76438,89883,92727,93084,157596,194979 %N A072896 5th-order digital invariants: the sum of the 5th powers of the digits of n equals some number k and the sum of the 5th powers of the digits of k equals n. %D A072896 David Wells, The Penguin Dictionary of Curious and Interesting Numbers, Revised Edition, London, England, 1997, pp. 157, 168. %e A072896 58618 is included because 5^5 + 8^5 + 6^5 + 1^5 + 8^5 = 76438 and 7^5 + 6^5 + 4^5 + 3^5 + 8^5 = 58618. %t A072896 f[n_] := Apply[Plus, IntegerDigits[Apply[Plus, IntegerDigits[n]^5]]^5]; Select[ Range[10^7], f[ # ] == # &] %t A072896 di5Q[n_]:=Module[{k=Total[IntegerDigits[n]^5]},Total[ IntegerDigits[k]^5] == n]; Select[Range[200000],di5Q] (* _Harvey P. Dale_, Nov 26 2014 *) %Y A072896 Cf. A072409. %K A072896 nonn,fini,full,base %O A072896 1,2 %A A072896 _Robert G. Wilson v_, Aug 09 2002