63648

Appears in sequences

• Number of closed meander systems of order n+1 with n components.at n=7A006659
• Triangle read by rows: T(n,k) = number of closed meander systems of order n with k<=n components.at n=43A008828
• Number of lines through at least 2 points of an n X n grid of points.at n=23A018808
• Theta series of A*_17 lattice.at n=77A023929
• Number of multigraphs with loops on 3 nodes with n edges.at n=31A050531
• Number of ways to place 2 nonattacking kings on an n X n board.at n=19A061995
• Expansion of (1+x^3*C)*C, where C = (1-(1-4*x)^(1/2))/(2*x) is g.f. for Catalan numbers, A000108.at n=11A071726
• G.f.: (1-16*x+28*x^2+56*x^3-140*x^4+56*x^5+28*x^6-16*x^7+x^8)/(x^2-x+1)^8.at n=11A112403
• Number of permutations of length n with exactly 4 occurrences of the pattern 2-13.at n=4A120812
• Coordination sequence for 6-dimensional cyclotomic lattice Z[zeta_18].at n=8A126900
• Triangle read by rows: T(n,k)=k*binomial(n-2k,3k+1) (n>=6, 0<=k<=(n-1)/5).at n=35A138779
• Convolution square of A058187, the tetrahedral series with repeats.at n=23A178440
• Number of 3-step king's tours on an n X n board summed over all starting positions.at n=34A186862
• G.f.: (1-4*x)^(-1/4) * (1-8*x)^(-1/8).at n=7A209358
• Sum of the divisors of n^3+1.at n=29A234645
• Number of preferential arrangements of n labeled elements such that the minimal number of elements per rank equals 7.at n=11A245860
• Triangle read by rows: T(n,k) (n>=0, 0<=k<=A002620(n-1)) is the number of permutations of [n] with k nestings.at n=47A263776
• Number of key comparisons to sort all n! permutations of n elements by the optimal quadral-pivot quicksort.at n=7A288971
• Triangle read by rows: T(n, k) is the number of walks of length n on the Z X Z grid with unit steps in all four directions (NSWE) starting at (0, 0). k is the absolute value of the x-coordinate of the endpoint of the walk.at n=47A380120
• Triangle read by rows: T(n,k) is the number of linear intervals of height k in the Tamari lattice Tam_n (0 <= k < n).at n=47A384133