A102393 A wicked evil sequence.

1, 0, 0, 4, 0, 6, 7, 0, 0, 10, 11, 0, 13, 0, 0, 16, 0, 18, 19, 0, 21, 0, 0, 24, 25, 0, 0, 28, 0, 30, 31, 0, 0, 34, 35, 0, 37, 0, 0, 40, 41, 0, 0, 44, 0, 46, 47, 0, 49, 0, 0, 52, 0, 54, 55, 0, 0, 58, 59, 0, 61, 0, 0, 64, 0, 66, 67, 0, 69, 0, 0, 72, 73, 0, 0, 76, 0, 78, 79, 0, 81, 0, 0, 84, 0, 86

Offset

0,4

Comments

Elements of A026147 (evil numbers plus one) appear at positions indexed by the evil numbers A001969, 0 otherwise. A000027(n) = A102393(n) + A102394(n).

The following sequences all appear to have the same parity: A003071, A029886, A061297, A092524, A093431, A102393, A104258, A122248, A128975. - Jeremy Gardiner, Dec 28 2008

Links

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

Tanya Khovanova, There are no coincidences, arXiv preprint 1410.2193 [math.CO], 2014.

Formula

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

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

Mathematica

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

Crossrefs

Cf. A000027, A000120, A001969, A010060, A026147, A102391, A102393, A102394.

Cf. A003071, A029886, A061297, A092524, A093431, A104258, A122248, A128975.

Sequence in context: A019629 A073759 A066760 * A228131 A370743 A019833

Adjacent sequences: A102390 A102391 A102392 * A102394 A102395 A102396

Keyword

easy,nonn

Author

Paul Barry, Jan 06 2005

Status

approved