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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). 4
 1, 2, 3, 4, 5, 6, 8, 9, 10, 12, 15, 16, 17, 18, 20, 23, 24, 27, 29, 30, 32, 33, 34, 36, 39, 40, 43, 45, 46, 48, 51, 53, 54, 57, 58, 60, 64, 65, 66, 68, 71, 72, 75, 77, 78, 80, 83, 85, 86, 89, 90, 92, 96, 99, 101, 102, 105, 106, 108, 113, 114, 116, 120, 128, 129, 130, 132, 135 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS Reinhard Zumkeller, Table of n, a(n) for n = 1..10000 FORMULA A209229(A000120(a(n))) = 1. - Reinhard Zumkeller, Sep 14 2014 EXAMPLE 34 in binary is 100010. This has 2 ones. And since 2 is a power of 2, 34 is included in the sequence. 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); # Emeric Deutsch, Aug 13 2008 MATHEMATICA Select[Range[150], IntegerQ[Log2[DigitCount[#, 2, 1]]]&] (* Harvey P. Dale, Sep 26 2020 *) PROG (Haskell) a143071 n = a143071_list !! (n-1) a143071_list = filter ((== 1) . a209229 . a000120) [1..] -- Reinhard Zumkeller, Sep 14 2014 CROSSREFS Cf. A000120, A143070, A143072, A209229. For complement see A271499. Sequence in context: A082415 A005236 A051250 * A305759 A143513 A062849 Adjacent sequences:  A143068 A143069 A143070 * A143072 A143073 A143074 KEYWORD base,nonn AUTHOR Leroy Quet, Jul 22 2008 EXTENSIONS More terms from Emeric Deutsch, Aug 13 2008 STATUS approved

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Last modified December 5 12:24 EST 2021. Contains 349557 sequences. (Running on oeis4.)