172824domain: NAppears in sequencesNumber of increasing sequences of n integers x(1),...,x(n) with values in 1..5*n such that x(j) divides x(k) iff j divides k.at n=36A180382a(n) = 6*(n - 1)*(81*n - 104) for n >= 1.at n=19A304837Expansion of Product_{k>=1} (1 - (x/(1+x))^k).at n=21A307548