A089312 Write n in binary; a(n) = number represented by rightmost block of 1's.

0, 1, 1, 3, 1, 1, 3, 7, 1, 1, 1, 3, 3, 1, 7, 15, 1, 1, 1, 3, 1, 1, 3, 7, 3, 1, 1, 3, 7, 1, 15, 31, 1, 1, 1, 3, 1, 1, 3, 7, 1, 1, 1, 3, 3, 1, 7, 15, 3, 1, 1, 3, 1, 1, 3, 7, 7, 1, 1, 3, 15, 1, 31, 63, 1, 1, 1, 3, 1, 1, 3, 7, 1, 1, 1, 3, 3, 1, 7, 15, 1, 1, 1, 3, 1, 1, 3, 7, 3, 1, 1, 3, 7, 1, 15, 31, 3, 1, 1, 3, 1

Offset

0,4

Links

Table of n, a(n) for n=0..100.

Example

13 = 1101 so a(13) = 1.

Mathematica

rb1[n_]:=Module[{id=Split[IntegerDigits[n, 2]]}, If[MemberQ[ Last[ id], 0], FromDigits[ id[[-2]], 2], FromDigits[id[[-1]], 2]]]; Join[{0}, Array[ rb1, 100]] (* Harvey P. Dale, Dec 18 2015 *)

Crossrefs

Cf. A089309-A089313.

a(2n+1) = A038712(n+1).

Sequence in context: A253223 A121745 A252983 * A246674 A363340 A058735

Adjacent sequences: A089309 A089310 A089311 * A089313 A089314 A089315

Keyword

nonn,base

Author

N. J. A. Sloane, Dec 22 2003

Extensions

More terms from Vladeta Jovovic, Jan 20 2004

Status

approved