559440

Appears in sequences

• a(n) = n^2*(n^2 - 1)/3.at n=36A112742
• Number of universes with n entities, exactly one being the empty set, which satisfy the Axiom of Extensionality (two sets are identical when they have the same elements) and are closed under taking subsets.at n=6A156972
• a(n) = Pell(n)*A008655(n) for n>=1, with a(0)=1, where A008655 lists the coefficients in (theta_3(x)*theta_3(3*x)+theta_2(x)*theta_2(3*x))^4.at n=6A209448
• a(n) is the smallest number with exactly n divisors that are Moran numbers, or -1 if no such number exists.at n=18A333457