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Position of rightmost 0 (including leading 0) in 2^n increases.
16

%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