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Positions of nonzero terms in A114592, the list of coefficients in the expansion of Product_{n > 1} (1 - 1/n^s).
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%I #5 Sep 16 2018 21:35:41

%S 1,2,3,4,5,7,9,11,12,13,17,18,19,20,23,24,25,28,29,30,31,32,36,37,40,

%T 41,42,43,44,45,47,48,49,50,52,53,54,56,59,60,61,63,66,67,68,70,71,72,

%U 73,75,76,78,79,80,83,84,88,89,90,92,97,98,99,100,101,102

%N Positions of nonzero terms in A114592, the list of coefficients in the expansion of Product_{n > 1} (1 - 1/n^s).

%t facs[n_]:=If[n<=1,{{}},Join@@Table[Map[Prepend[#,d]&,Select[facs[n/d],Min@@#>=d&]],{d,Rest[Divisors[n]]}]];

%t Join@@Position[Table[Sum[(-1)^Length[f],{f,Select[facs[n],UnsameQ@@#&]}],{n,100}],_Integer?(Abs[#]>0&)]

%Y Complement of A319238.

%Y Cf. A001055, A045778, A114592, A162247, A190938, A281116, A281118, A303386, A316441, A319239.

%K nonn

%O 1,2

%A _Gus Wiseman_, Sep 15 2018