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%I #5 Nov 13 2019 15:09:19
%S 0,1,1,3,2,6,4,10,9,15,14,29,24,39,44,65,66,102,105,154,170,225,253,
%T 356,385,503,583,749,847,1100,1238,1572,1809,2234,2579,3219,3660,4484,
%U 5195,6314,7245,8800,10087,12141,14011,16678,19196,22930,26256,31099,35784
%N Expansion of Sum_{k>=1} (-1 + Product_{j>=2} 1 / (1 - x^(k*j))).
%C Inverse Moebius transform of A002865.
%F G.f.: Sum_{k>=1} A002865(k) * x^k / (1 - x^k).
%F a(n) = Sum_{d|n} A002865(d).
%t nmax = 51; CoefficientList[Series[Sum[-1 + Product[1/(1 - x^(k j)), {j, 2, nmax}], {k, 1, nmax}], {x, 0, nmax}], x] // Rest
%Y Cf. A002865, A047966, A047968, A329436.
%K nonn
%O 1,4
%A _Ilya Gutkovskiy_, Nov 13 2019