A173022 Number of numbers <= n having no isolated ones in their binary representations.

1, 1, 1, 2, 2, 2, 3, 4, 4, 4, 4, 4, 5, 5, 6, 7, 7, 7, 7, 7, 7, 7, 7, 7, 8, 8, 8, 9, 10, 10, 11, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 13, 13, 13, 14, 14, 14, 15, 16, 17, 17, 17, 18, 19, 19, 20, 21, 21, 21, 21, 21, 21, 21, 21, 21, 21, 21, 21, 21, 21, 21, 21

Offset

0,4

Comments

a(A144795(n+1)) = a(A144795(n)) + 1;

a(2^n - 1)) = A005251(n+1);

A173021(n) <= a(n) <= A173023(n).

Links

R. Zumkeller, Table of n, a(n) for n = 0..10000

Example

a(20)=#{0,3,6,7,12,14,15}=#{0,11,110,111,1100,1110,1111}=7.

Crossrefs

Sequence in context: A228482 A091822 A358178 * A060973 A352228 A097915

Adjacent sequences: A173019 A173020 A173021 * A173023 A173024 A173025

Keyword

base,nonn

Author

Reinhard Zumkeller, Feb 07 2010

Status

approved