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

15, 25, 41, 45, 47, 65, 71, 73, 76, 82, 85, 95, 97, 100, 110, 112, 118, 120, 132, 137, 143, 145, 147, 151, 154, 156, 158, 160, 162, 164, 170, 179, 180, 185, 195, 196, 201, 214, 216, 219, 225, 227, 233, 235, 238, 251, 252, 275, 284, 290, 295, 297, 301, 304

Offset

1,1

Comments

If there is a term beyond a(108)=1862 it is larger than 10^5. - Giovanni Resta, Oct 14 2019

Links

Giovanni Resta, Table of n, a(n) for n = 1..108

Example

2^15 = {32}768;
2^25 = 335544{32};
2^41 = 219902{32}55552.

Mathematica

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 *)

Crossrefs

Cf. A033921.

Sequence in context: A133321 A031888 A299469 * A354959 A280406 A020302

Adjacent sequences: A046288 A046289 A046290 * A046292 A046293 A046294

Keyword

nonn,base

Author

Patrick De Geest, Jun 15 1998

Status

approved