A143072 A positive integer n is included if both the number of 0's and the number of 1's in the binary representation of n are powers of 2 (including being possibly 1).

2, 4, 5, 6, 9, 10, 12, 16, 23, 27, 29, 30, 33, 34, 36, 39, 40, 43, 45, 46, 48, 51, 53, 54, 57, 58, 60, 135, 139, 141, 142, 147, 149, 150, 153, 154, 156, 163, 165, 166, 169, 170, 172, 177, 178, 180, 184, 195, 197, 198, 201, 202, 204, 209, 210, 212, 216, 225, 226, 228

Offset

1,1

Links

Reinhard Zumkeller, Table of n, a(n) for n = 1..10000

Formula

A209229(A000120(a(n))) * A209229(A023416(a(n))) = 1. - Reinhard Zumkeller, Sep 14 2014

Example

34 in binary is 100010. This has 4 zeros and 2 ones. And since 4 and 2 are both powers of 2, 34 is included in the sequence.

Mathematica

p2Q[n_]:=And@@(IntegerQ[Log[2, #]]&/@DigitCount[n, 2]); Select[Range[250], p2Q] (* Harvey P. Dale, Aug 20 2013 *)

Prog

(Haskell)
a143072 n = a143072_list !! (n-1)
a143072_list = filter ((== 1) . a209229 . a023416) a143071_list
-- Reinhard Zumkeller, Sep 14 2014

Crossrefs

Cf. A023416, A000120, A143070, A143071.

Cf. A209229.

Sequence in context: A352508 A125297 A194469 * A089648 A062861 A120629

Adjacent sequences: A143069 A143070 A143071 * A143073 A143074 A143075

Keyword

base,nonn,look

Author

Leroy Quet, Jul 22 2008

Extensions

Extended by Ray Chandler, Jun 20 2009

Status

approved