251498

Appears in sequences

• Triangle of central factorial numbers T(2*n,2*n-2*k), k >= 0, n >= 1 (in Riordan's notation).at n=39A008957
• a(n) = 3*a(n-1) + a(n-2) - a(n-3) for n >= 3, a(0)=1, a(1)=2, a(2)=7.at n=11A030186
• Number of matchings in graph P_{11} X P_{n}.at n=2A033514
• Triangle read by rows: T(n,k) = T(n-1,k-1) + k^2*T(n-1,k), 1 < k <= n, T(n,1) = 1.at n=41A036969
• Triangle read by rows. Stirling set numbers of order 2, T(n, n) = 1, T(n, k) = 0 if k < 0 or k > n, otherwise T(n, k) = T(n-1, k-1) + k^2*T(n-1, k), for 0 <= k <= n.at n=51A269945
• a(n) = [x^n] Product_{k=1..2*n} 1/(1 - k^2 * x).at n=3A348081
• a(n) = Sum_{k=1..n} Sum_{j=1..k} Sum_{i=1..j} (i*j*k)^2.at n=6A351105
• a(2*n) = A030186(n), a(2*n+1) = A033505(n).at n=22A365967