A039308 Numbers whose base-7 representation has the same nonzero number of 0's and 1's.

7, 51, 52, 53, 54, 55, 63, 70, 77, 84, 91, 99, 105, 148, 154, 197, 203, 246, 252, 295, 301, 344, 350, 359, 360, 361, 362, 363, 366, 367, 368, 369, 370, 373, 374, 375, 376, 377, 380, 381, 382, 383, 384, 387, 388, 389, 390, 391, 392, 443, 444, 445, 446, 447

Offset

1,1

Links

Robert Israel, Table of n, a(n) for n = 1..10000

Maple

filter:= proc(n) local L, t;
  L:= convert(n, base, 7);
  t:= numboccur(0, L);
  t=numboccur(1, L) and t>0
end proc:
select(filter, [$1..447]); # Robert Israel, Jul 18 2018

Mathematica

Select[Range[500], DigitCount[#, 7, 0]==DigitCount[#, 7, 1]>0&] (* Harvey P. Dale, Jun 21 2019 *)

Crossrefs

Cf. A007093.

Sequence in context: A320989 A015495 A056581 * A029525 A037500 A037677

Adjacent sequences: A039305 A039306 A039307 * A039309 A039310 A039311

Keyword

nonn,base,easy

Author

Olivier Gérard

Status

approved