13728792

Appears in sequences

• Number of tree-rooted bridgeless planar maps with two vertices and n faces.at n=13A002740
• a(n) = lcm{1, ..., 2n} / binomial(2n, n).at n=24A068550
• Numbers that can be expressed as the difference of the squares of primes in exactly twenty distinct ways.at n=17A092016
• Denominators of first derivatives of Catalan numbers (as continuous functions of n).at n=23A260631
• a(n) = lcm{1,2,...,n} / binomial(n,floor(n/2)).at n=48A263673
• Triangle read by rows. T(n, k) = (1/2) * C(n, k) * C(3*n - 1, n) for n > 0 and T(0, 0) = 1.at n=39A360560
• Triangle read by rows. T(n, k) = (1/2) * C(n, k) * C(3*n - 1, n) for n > 0 and T(0, 0) = 1.at n=41A360560