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 A137201 #11 Feb 06 2021 17:48:27 %S A137201 342,438,546,666,685,798,942,950,1028,1098,1266,1275,1371,1446,1462, %T A137201 1638,1666,1714,1842,1974,2004,2057,2058,2129,2286,2394,2395,2396, %U A137201 2397,2398,2399,2400,2486,2526,2666,2670,2733,2743,2778,2998,3042,3086,3295 %N A137201 "Ungodly" numbers: numbers that, in some base b > 6, contain the string 666 at least once in their expansion. %C A137201 _Max Alekseyev_ asked if there are an infinite number of godly numbers. %H A137201 Joshua Zucker, Mar 04 2008, <a href="/A137201/b137201.txt">Table of n, a(n) for n = 1..2938</a> %e A137201 342 is in the sequence because 342 = 666_7. %e A137201 685 is in the sequence because 685 = 1666_7. %e A137201 99968 is in the sequence because 99968 = 3666B_13. %Y A137201 Cf. A121205 (numbers that in some base b are represented exactly as 666, so it is a subsequence of this sequence). %K A137201 base,nonn %O A137201 1,1 %A A137201 _Joshua Zucker_, Mar 04 2008