The On-Line Encyclopedia of Integer Sequences (OEIS)

Revision History for A143071 (Bold, blue-underlined text is an addition; faded, red-underlined text is a ~~deletion~~.)
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A143071

A positive integer n is included if the number of 1's in the binary representation of n is a power of 2 (including being possibly 1).
(history; published version)

#15 by Harvey P. Dale at Sat Sep 26 14:53:05 EDT 2020

STATUS

editing

approved

#14 by Harvey P. Dale at Sat Sep 26 14:53:01 EDT 2020

MATHEMATICA

Select[Range[150], IntegerQ[Log2[DigitCount[#, 2, 1]]]&] (* Harvey P. Dale, Sep 26 2020 *)

STATUS

approved

editing

#13 by N. J. A. Sloane at Sat Apr 16 05:11:06 EDT 2016

STATUS

editing

approved

#12 by N. J. A. Sloane at Sat Apr 16 05:11:03 EDT 2016

CROSSREFS

Cf. A000120, A143070, A143072, A209229.

Cf. A209229.

For complement see A271499.

STATUS

approved

editing

#11 by Jon E. Schoenfield at Mon Jul 13 21:08:44 EDT 2015

STATUS

editing

approved

#10 by Jon E. Schoenfield at Mon Jul 13 21:08:42 EDT 2015

MAPLE

a:=proc(n) local nn, n1: nn:=convert(n, base, 2): n1:=add(nn[j], j=1..nops(nn)): if 0 < n1 and type(log[2](n1), integer)=true then n else end if end proc: seq(a(n), n=1..140); [From _# _Emeric Deutsch_, Aug 13 2008]

STATUS

approved

editing

#9 by Reinhard Zumkeller at Sun Sep 14 16:09:43 EDT 2014

STATUS

editing

approved

#8 by Reinhard Zumkeller at Sun Sep 14 15:39:40 EDT 2014

FORMULA

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

CROSSREFS

Cf. A209229.