-49680domain: ZAppears in sequencesG.f. L(x,y) satisfies: L(x,y) = x * (1 + y*x*L'(x,y)) / (1 + x*L'(x,y)) where L'(x,y) = d/dx L(x,y), as a triangle read by rows.at n=28A301305Expansion of Sum_{k>=1} x^k/(1 + k*x^k).at n=31A308367a(n) = Sum_{d|n} (-1)^(d-1) * d^(n/d-1).at n=31A359812