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A230048 Squarefree odious numbers. 1

%I #17 Mar 15 2024 02:25:43

%S 1,2,7,11,13,14,19,21,22,26,31,35,37,38,41,42,47,55,59,61,62,67,69,70,

%T 73,74,79,82,87,91,93,94,97,103,107,109,110,115,118,122,127,131,133,

%U 134,137,138,143,145,146,151,155,157,158,161,167,173,174,179,181,182,185,186,191,193,194,199

%N Squarefree odious numbers.

%C Odious numbers that are squarefree numbers.

%H Amiram Eldar, <a href="/A230048/b230048.txt">Table of n, a(n) for n = 1..10000</a>

%t odiousQ[n_] := OddQ @ DigitCount[n, 2][[1]]; Select[Range[200], odiousQ[#] && SquareFreeQ[#] &] (* _Amiram Eldar_, Dec 10 2019 *)

%o (PARI) is(n)=hammingweight(n)%2 && issquarefree(n) \\ _Charles R Greathouse IV_, Mar 18 2014

%Y Intersection of A000069 and A005117.

%K nonn,base

%O 1,2

%A _Irina Gerasimova_, Oct 06 2013

%E Corrected by _R. J. Mathar_, Oct 06 2013

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Last modified August 23 08:17 EDT 2024. Contains 375375 sequences. (Running on oeis4.)