%I #5 May 11 2022 22:46:36
%S 1,1,1,1,2,-2,4,-3,4,-6,14,-18,30,-32,48,-73,128,-182,286,-394,578,
%T -804,1386,-1936,3172,-4298,7102,-10202,16414,-23798,38056,-54997,
%U 86658,-125180,203396,-292650,475536,-685314,1100728,-1619952,2601166,-3808952,6114666,-9045400,14352568
%N Product_{n>=1} (1 + a(n)*x^n) = 1 + Sum_{n>=1} phi(n)*x^n, where phi = A000010.
%t A[m_, n_] := A[m, n] = Which[m == 1, EulerPhi[n], m > n >= 1, 0, True, A[m - 1, n] - A[m - 1, m - 1] A[m, n - m + 1]]; a[n_] := A[n, n]; a /@ Range[1, 45]
%Y Cf. A000010, A320778, A328774, A353923, A353924, A353926.
%K sign
%O 1,5
%A _Ilya Gutkovskiy_, May 11 2022
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