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A145255 a(n) = the smallest positive integer that is non-coprime to n and has the same number of 0's in its binary representation as n has. 4

%I #13 Oct 27 2017 15:19:22

%S 2,3,4,5,2,7,8,9,4,11,4,13,2,3,16,17,8,19,8,9,4,23,8,10,4,6,4,29,2,31,

%T 32,33,16,20,16,37,8,9,16,41,8,43,8,9,4,47,16,35,8,9,8,53,4,5,8,9,4,

%U 59,4,61,2,3,64,65,32,67,32,33,16,71,32,73,16,18,16,35,8,79,32,33,16,83,16

%N a(n) = the smallest positive integer that is non-coprime to n and has the same number of 0's in its binary representation as n has.

%H Michael De Vlieger, <a href="/A145255/b145255.txt">Table of n, a(n) for n = 2..16384</a>

%t Table[Function[k, SelectFirst[Range[2, n], And[! CoprimeQ[#, n], DigitCount[#, 2, 0] == k] &]]@ DigitCount[n, 2, 0], {n, 2, 84}] (* _Michael De Vlieger_, Oct 26 2017 *)

%Y Cf. A145254, A145256, A145257.

%K nonn,look,base

%O 2,1

%A _Leroy Quet_, Oct 05 2008

%E Extended by _Ray Chandler_, Nov 03 2008

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Last modified April 25 16:45 EDT 2024. Contains 371989 sequences. (Running on oeis4.)