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A046291 Numbers k such that 2^k contains 2^5=32 as its largest proper substring of the form 2^m.

%I A046291 #18 Oct 14 2019 05:08:13
%S A046291 15,25,41,45,47,65,71,73,76,82,85,95,97,100,110,112,118,120,132,137,
%T A046291 143,145,147,151,154,156,158,160,162,164,170,179,180,185,195,196,201,
%U A046291 214,216,219,225,227,233,235,238,251,252,275,284,290,295,297,301,304
%N A046291 Numbers k such that 2^k contains 2^5=32 as its largest proper substring of the form 2^m.
%C A046291 If there is a term beyond a(108)=1862 it is larger than 10^5. - _Giovanni Resta_, Oct 14 2019
%H A046291 Giovanni Resta, <a href="/A046291/b046291.txt">Table of n, a(n) for n = 1..108</a>
%e A046291 2^15 = {32}768;
%e A046291 2^25 = 335544{32};
%e A046291 2^41 = 219902{32}55552.
%t A046291 sub2[n_] := Block[{s = ToString[2^n], k = n - 1}, While[k >= 0 && ! StringContainsQ[s, ToString[2^k]], k--]; k]; Select[Range[2000], sub2[#] == 5 &] (* _Giovanni Resta_, Oct 14 2019 *)
%Y A046291 Cf. A033921.
%K A046291 nonn,base
%O A046291 1,1
%A A046291 _Patrick De Geest_, Jun 15 1998