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%I #14 Dec 02 2019 04:11:42
%S 1,2,3,4,5,7,8,11,13,15,16,17,19,21,23,25,27,29,31,32,33,35,37,39,41,
%T 43,47,49,50,51,53,55,57,59,61,64,65,67,69,71,73,77,79,81,83,85,87,89,
%U 91,93,95,97,98,100,101,103,105,107,109,111,113,115,119,121,123,125,127,128,129,131,133,135,137,139,141,143,145,149,151,155
%N Numbers coprime to the number of their odd divisors.
%C Contains A046642.
%C Conjecture: the asymptotic density of this sequence is the same as that of A046642.
%H Amiram Eldar, <a href="/A269870/b269870.txt">Table of n, a(n) for n = 1..10000</a>
%e For n=2, a(2)=2 is a term as the number of odd divisors of 2 is 1, which is coprime to 2.
%t Select[Range@200, CoprimeQ[#, Length@Select[Divisors[#], OddQ]]&]
%o (PARI) for(n=1, 200, gcd(n, sumdivmult(n, d, d%2))==1&&print1(n, ", "))
%Y Cf. A001227 (number of odd divisors), A046642 (numbers coprime to the number of their divisors), A269818 (counterpart for the number of even divisors).
%K nonn
%O 1,2
%A _Waldemar Puszkarz_, Mar 06 2016
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