A165316 a(n) = the number of digits in the binary representation of n that each either precede and/or follow a similarly valued digit.

0, 0, 2, 2, 0, 2, 3, 3, 2, 0, 2, 4, 2, 3, 4, 4, 3, 2, 4, 2, 0, 2, 3, 5, 4, 2, 4, 5, 3, 4, 5, 5, 4, 3, 5, 4, 2, 4, 5, 3, 2, 0, 2, 4, 2, 3, 4, 6, 5, 4, 6, 4, 2, 4, 5, 6, 5, 3, 5, 6, 4, 5, 6, 6, 5, 4, 6, 5, 3, 5, 6, 5, 4, 2, 4, 6, 4, 5, 6, 4, 3, 2, 4, 2, 0, 2, 3, 5, 4, 2, 4, 5, 3, 4, 5, 7, 6, 5, 7, 6, 4, 6, 7, 5, 4

Offset

1,3

Links

John Tyler Rascoe, Table of n, a(n) for n = 1..8191

Example

184 in binary is 10111001. There are exactly five binary digits (the 2nd, 3rd, and 4th 1's from the left, and the 2nd and 3rd 0's from the left) that are each adjacent to a similar digit. So a(184) = 5.

Crossrefs

Cf. A165317.

Sequence in context: A241533 A370885 A072738 * A362991 A215976 A141058

Adjacent sequences: A165313 A165314 A165315 * A165317 A165318 A165319

Keyword

base,nonn,easy

Author

Leroy Quet, Sep 14 2009

Extensions

Extended by Ray Chandler, Mar 13 2010

Status

approved