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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).
3

%I #12 Sep 14 2014 16:10:32

%S 2,4,5,6,9,10,12,16,23,27,29,30,33,34,36,39,40,43,45,46,48,51,53,54,

%T 57,58,60,135,139,141,142,147,149,150,153,154,156,163,165,166,169,170,

%U 172,177,178,180,184,195,197,198,201,202,204,209,210,212,216,225,226,228

%N 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).

%H Reinhard Zumkeller, <a href="/A143072/b143072.txt">Table of n, a(n) for n = 1..10000</a>

%F A209229(A000120(a(n))) * A209229(A023416(a(n))) = 1. - _Reinhard Zumkeller_, Sep 14 2014

%e 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.

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

%o (Haskell)

%o a143072 n = a143072_list !! (n-1)

%o a143072_list = filter ((== 1) . a209229 . a023416) a143071_list

%o -- _Reinhard Zumkeller_, Sep 14 2014

%Y Cf. A023416, A000120, A143070, A143071.

%Y Cf. A209229.

%K base,nonn,look

%O 1,1

%A _Leroy Quet_, Jul 22 2008

%E Extended by _Ray Chandler_, Jun 20 2009