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 A270040 #13 Mar 10 2016 20:55:15
%S A270040 10,11,12,13,15,15,17,17,66,75,75,86,86,90,138,138,138,138,138,138,
%T A270040 138,138,138,182,182,182,182,182,182,182,182,182,185,781817578165,
%U A270040 781817578165,7826560751018861596150680
%N A270040 a(n) = Smallest m >= 9 containing no fours when represented in any base from 5 through n.
%C A270040 It remains to be determined if the sequence is finite.
%C A270040 These numbers are not very Foury, at least not initially. (See A268236.)
%H A270040 Nathan Fox, <a href="/A270040/b270040.txt">Table of n, a(n) for n = 5..59</a>
%t A270040 Table[SelectFirst[Range[9, 10^3], Total@ Map[Function[k, DigitCount[#, k, 4]], Range[5, n]] == 0 &], {n, 5, 60}] /. n_ /; MissingQ@ n -> Nothing (* _Michael De Vlieger_, Mar 10 2016, Version 10.2 *)
%Y A270040 Cf. A268236, A268237, A270030, A270037, A270038, A216192, A270039, A270041, A270042, A270043, A270044, A270045.
%K A270040 nonn,base
%O A270040 5,1
%A A270040 _Nathan Fox_, Mar 09 2016