A004763 Numbers whose binary expansion does not begin 101.

0, 1, 2, 3, 4, 6, 7, 8, 9, 12, 13, 14, 15, 16, 17, 18, 19, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 96, 97, 98, 99

Offset

1,3

Links

Table of n, a(n) for n=1..69.

Formula

a(1) = 0, a(2) = 1, a(3) = 2, a(2^m+k+2) = 2^m + 2^(m-1) + k, m >= 1, 0 <= k < 2^m. - Yosu Yurramendi, Aug 08 2016

Mathematica

w = {1, 0, 1}; Select[Range[0, 99], If[# < 2^(Length@ w - 1), True, Take[IntegerDigits[#, 2], Length@ w] != w] &] (* Michael De Vlieger, Aug 10 2016 *)

Crossrefs

Cf. A007088.

Sequence in context: A113508 A059325 A258938 * A320456 A330060 A330108

Adjacent sequences: A004760 A004761 A004762 * A004764 A004765 A004766

Keyword

nonn,easy,base

Author

N. J. A. Sloane

Status

approved