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A099247 Numbers such that, in binary representation, the length and the number of ones are coprime. 4

%I #14 Oct 10 2013 16:19:36

%S 1,2,4,5,6,8,11,13,14,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,32,

%T 47,55,59,61,62,64,65,66,67,68,69,70,71,72,73,74,75,76,77,78,79,80,81,

%U 82,83,84,85,86,87,88,89,90,91,92,93,94,95,96,97,98,99,100,101,102,103

%N Numbers such that, in binary representation, the length and the number of ones are coprime.

%C A099244(a(n)) = 1; complement of A099248.

%H Reinhard Zumkeller, <a href="/A099247/b099247.txt">Table of n, a(n) for n = 1..10000</a>

%H <a href="/index/Bi#binary">Index entries for sequences related to binary expansion of n</a>

%t Select[Range[150],CoprimeQ[IntegerLength[#,2],DigitCount[#,2,1]]&] (* _Harvey P. Dale_, Sep 22 2012 *)

%o (Haskell)

%o a099247 n = a099247_list !! (n-1)

%o a099247_list = filter ((== 1) . a099244) [1..]

%o -- _Reinhard Zumkeller_, Oct 10 2013

%Y Cf. A099249, A070939, A000120, A007088.

%K nonn

%O 1,2

%A _Reinhard Zumkeller_, Oct 08 2004

%E Definition clarified by _Harvey P. Dale_, Sep 22 2012

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Last modified June 6 18:47 EDT 2024. Contains 373134 sequences. (Running on oeis4.)