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 A226971 #20 Dec 13 2024 11:00:05 %S A226971 0,1,18,27,31,34,43,53,58,68 %N A226971 Numbers k such that the sum of digits of k^7 is equal to k. %C A226971 Only the ten integers listed have this property. %e A226971 a(3) = 18 because 18^7 = 612220032 and 6+1+2+2+2+0+0+3+2 = 18. %t A226971 Select[Range[0, 100], #==Total[IntegerDigits[#^7]]&] %o A226971 (Magma) [n: n in [0..80] | &+Intseq(n^7) eq n]; // _Vincenzo Librandi_, Feb 23 2015 %o A226971 (Sage) [n for n in (0..70) if sum((n^7).digits()) == n] # _Bruno Berselli_, Feb 23 2015 %o A226971 (PARI) isok(k)=sumdigits(k^7)==k \\ _Patrick De Geest_, Dec 13 2024 %Y A226971 Cf. A046459, A055575, A055576, A055577. %Y A226971 Cf. A152147. %K A226971 nonn,base,fini,full %O A226971 1,3 %A A226971 _Michel Lagneau_, Jun 24 2013