81124680

Appears in sequences

• Numbers n such that the multiplicative group modulo n is the direct product of 9 cyclic groups.at n=11A272599
• Triangle read by rows in which row(n) = {T(n, k)} is the lexicographically earliest list of n numbers such that adding 1 to some T(n, k) gives a row of numbers each divisible by prime(k).at n=40A286947
• a(n) = sigma(2*n) * binomial(2*n,n)/2, for n >= 1.at n=11A322185