login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A046291 Numbers k such that 2^k contains 2^5=32 as its largest proper substring of the form 2^m. 1

%I #18 Oct 14 2019 05:08:13

%S 15,25,41,45,47,65,71,73,76,82,85,95,97,100,110,112,118,120,132,137,

%T 143,145,147,151,154,156,158,160,162,164,170,179,180,185,195,196,201,

%U 214,216,219,225,227,233,235,238,251,252,275,284,290,295,297,301,304

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

%C If there is a term beyond a(108)=1862 it is larger than 10^5. - _Giovanni Resta_, Oct 14 2019

%H Giovanni Resta, <a href="/A046291/b046291.txt">Table of n, a(n) for n = 1..108</a>

%e 2^15 = {32}768;

%e 2^25 = 335544{32};

%e 2^41 = 219902{32}55552.

%t 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 Cf. A033921.

%K nonn,base

%O 1,1

%A _Patrick De Geest_, Jun 15 1998

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified April 24 22:17 EDT 2024. Contains 371964 sequences. (Running on oeis4.)