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