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 A031142 #58 Oct 11 2019 21:21:39
%S A031142 0,4,7,13,14,18,24,27,31,34,37,49,51,67,72,76,77,81,86,129,176,229,
%T A031142 700,1757,1958,7931,57356,269518,411658,675531,749254,4400728,
%U A031142 18894561,33250486,58903708,297751737,325226398,781717865,18504580518,27893737353
%N A031142 Position of rightmost 0 (including leading 0) in 2^n increases.
%C A031142 "Positions" are counted 0,1,2,3,... starting with the least significant digit.
%C A031142 86 is the last n for which the rightmost zero is the leading zero.
%H A031142 Alan Griffiths, <a href="/A031142/b031142.txt">Table of n, a(n) for n = 1..46</a> (reuploaded from a-file by _Georg Fischer_, Jan 21 2019)
%t A031142 best = 0;
%t A031142 Select[Range[0, 10000],
%t A031142 If[(t = First@
%t A031142 First@StringPosition[StringReverse@("0" <> ToString@(2^#)),
%t A031142 "0"]) > best, best = t; True] &] (* _Robert Price_, Oct 11 2019 *)
%Y A031142 Cf. A031140, A031141, A031142, A031143.
%K A031142 nonn,base
%O A031142 1,2
%A A031142 _Matthew Cook_, _Dan Hoey_, _Eric W. Weisstein_, _David W. Wilson_
%E A031142 a(39)-a(41) added (to match A031140) by _Tanya Khovanova_, Feb 02 2011
%E A031142 a(42)-a(44) from _Alan Griffiths_, Jan 25 2012