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%I #5 Jan 14 2024 15:06:44
%S 2,3,5,6,7,8,10,11,13,14,17,18,19,22,23,24,26,27,29,30,31,32,34,37,38,
%T 40,41,42,43,45,46,47,50,53,54,56,58,59,61,62,63,66,67,70,71,72,73,74,
%U 75,78,79,82,83,86,88,89,90,94,96,97,98,99,101,102,103,104,105,106,107,109,110,113,114,117,118,120,122,125
%N Numbers k for which A342001(k) is odd.
%o (PARI)
%o A003415(n) = if(n<=1, 0, my(f=factor(n)); n*sum(i=1, #f~, f[i, 2]/f[i, 1]));
%o A003557(n) = (n/factorback(factorint(n)[, 1]));
%o A342001(n) = (A003415(n) / A003557(n));
%o isA368999(n) = (A342001(n)%2);
%Y Cf. A342001.
%Y Positions of 0's in A368997. Cf. A368999 (complement).
%K nonn
%O 1,1
%A _Antti Karttunen_, Jan 14 2024