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A165316
a(n) = the number of digits in the binary representation of n that each either precede and/or follow a similarly valued digit.
2
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
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
KEYWORD
base,nonn,easy
AUTHOR
Leroy Quet, Sep 14 2009
EXTENSIONS
Extended by Ray Chandler, Mar 13 2010
STATUS
approved