A102394 A wicked odious sequence.

0, 2, 3, 0, 5, 0, 0, 8, 9, 0, 0, 12, 0, 14, 15, 0, 17, 0, 0, 20, 0, 22, 23, 0, 0, 26, 27, 0, 29, 0, 0, 32, 33, 0, 0, 36, 0, 38, 39, 0, 0, 42, 43, 0, 45, 0, 0, 48, 0, 50, 51, 0, 53, 0, 0, 56, 57, 0, 0, 60, 0, 62, 63, 0, 65, 0, 0, 68, 0, 70, 71, 0, 0, 74, 75, 0, 77, 0, 0, 80, 0, 82, 83, 0, 85, 0

Offset

0,2

Comments

Odious numbers plus one (A000069(n)+1) appear at positions indexed by the odious numbers, 0 otherwise. A000027(n) = A102393(n) + A102394(n).

Links

Table of n, a(n) for n=0..85.

Formula

a(n) = (n+1)(1-(-1)^A000120(n))/2.

a(n) = (n+1)(1-(-1)^A010060(n))/2.

Mathematica

a[n_] := If[OddQ @ DigitCount[n, 2, 1], n + 1, 0]; Array[a, 100, 0] (* Amiram Eldar, Aug 02 2020 *)

Crossrefs

Cf. A000027, A000069, A000120, A010060, A102392, A102393.

Sequence in context: A211402 A256064 A126436 * A145091 A085563 A071375

Adjacent sequences: A102391 A102392 A102393 * A102395 A102396 A102397

Keyword

easy,nonn

Author

Paul Barry, Jan 06 2005

Status

approved