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A305353 Expansion of Product_{k>=1} (1 - x^phi(k)), where phi is Euler's totient function.

%I A305353 #14 May 12 2022 13:10:15
%S A305353 1,-2,-2,6,-4,2,6,-14,8,-2,4,-6,-16,38,-22,6,2,-10,2,6,60,-126,28,70,
%T A305353 -38,6,-38,70,-54,38,18,-74,-70,214,106,-426,186,54,-26,-2,-92,186,
%U A305353 -218,250,-66,-118,-104,326,466,-1258,500,258,-254,250,-368,486,-342,198
%N A305353 Expansion of Product_{k>=1} (1 - x^phi(k)), where phi is Euler's totient function.
%F A305353 Product_{k>=1} (1 - x^k)^A014197(k).
%t A305353 terms = 58;
%t A305353 S[m_] := S[m] = CoefficientList[Product[1 - x^EulerPhi[k],
%t A305353      {k, 1, m*terms}] + O[x]^terms, x];
%t A305353 S[m = 1];
%t A305353 S[m++];
%t A305353 While[S[m] != S[m - 1], m++];
%t A305353 S[m] (* _Jean-François Alcover_, May 12 2022 *)
%Y A305353 Cf. A000010 (phi), A014197, A120963, A280611.
%K A305353 sign
%O A305353 0,2
%A A305353 _Seiichi Manyama_, May 31 2018