391285

Appears in sequences

• Expansion of e.g.f. exp(-x)/(1-2*x).at n=7A000354
• Square array T(n,k) (row n, column k) read by antidiagonals defined by: T(n,k) is the permanent of the n X n matrix with 1 on the diagonal and k elsewhere; T(0,k)=1.at n=52A090628
• Number of n X n binary matrices, symmetric under horizontal and vertical reflection, with no more than 2 ones in any 2 X 2 subblock.at n=10A141504
• Form the difference table of the sequence {2^k*k!}, then divide k-th column entries by 2^k*k!. Array read by ascending antidiagonals, T(n, k) for n, k >= 0.at n=28A143410
• Square array A(n,k), n >= 0, k >= 0, read by antidiagonals, where column k is the expansion of the e.g.f. exp(-x)/(1 - k*x).at n=52A320032
• Double subfactorials: a(n) = (-1)^floor(n/2) * n!! * Sum_{i=0..floor(n/2)} (-1)^i/(n-2*i)!!.at n=14A334578
• Triangle read by rows: T(n,k) is the number of symmetries of the n-dimensional hypercube that fix exactly 2*k facets; n,k >= 0.at n=28A342381
• Triangle read by rows: T(n, k) = n! * 2^k * hypergeom([-k], [-n], -1/2).at n=35A374427