1056720

Appears in sequences

• Numbers that can be expressed as the difference of the squares of primes in exactly twelve distinct ways.at n=25A092008
• If X_1,...,X_n is a partition of a 2n-set X into 2-blocks then a(n) is equal to the number of 4-subsets of X containing none of X_i, (i=1,...,n).at n=33A130810
• E.g.f. A(x) satisfies A(x) = exp( x^2 * A(x) / (1-x)^2 ) / (1-x).at n=7A389867