549900domain: NAppears in sequencesExpansion of e.g.f. sin(log(1+x)).at n=10A009454a(n) = n*(n+1)*(n^2 - 3*n + 6)/4.at n=39A062026Imaginary part of Product_{k=0..n} (i-k), where i=sqrt(-1).at n=9A242652