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
Examples
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.
Links
- John Tyler Rascoe, Table of n, a(n) for n = 1..8191
Crossrefs
Cf. A165317.
Extensions
Extended by Ray Chandler, Mar 13 2010