39587

Appears in sequences

• Number of restricted hexagonal polyominoes with n cells.at n=9A002212
• Number of polyhexes with n hexagons, having reflectional symmetry (see Harary and Read for precise definition).at n=17A002215
• a(n) = a(1)*a(n-1) + a(2)*a(n-2) + ...+ a(n-2)*a(2) for n >= 3.at n=9A025238
• Catafusenes (see reference for precise definition).at n=17A044044
• Path-counting array T; each step of a path is (1 right) or (1 up) to a point below line y=x, else (1 right and 1 up) or (1 up) to a point on the line y=x, else (1 left) or (1 up) to a point above line y=x. T(i,j)=number of paths to point (i-j,j), for 1<=j<=i, i >= 1.at n=44A055450
• Triangle of numbers arising in recursive computation of A002212.at n=45A073149
• Triangular array related to Motzkin triangle A026300.at n=44A084536
• Triangle read by rows: T(n,k) = number of lattice paths from (0,0) to (n,k) that do not go below the line y=0 and consist of steps U=(1,1), D=(1,-1) and three types of steps H=(1,0) (left factors of 3-Motzkin steps).at n=36A091965
• Triangle read by rows: T(n,k) is the number of Schroeder paths of length 2n and having k peaks at odd height.at n=45A101894
• Sum array of Catalan numbers (A000108) read by upward antidiagonals.at n=46A106534
• Triangle read by rows: T(n,k) is number of hex trees with n edges and level of first leaf (in the preorder traversal) equal to k (1 <= k <= n).at n=45A126186
• Triangle read by rows: T(n,k) is the number of skew Dyck paths of semilength n and having height of the first peak equal to k (1 <= k <= n).at n=45A128744
• Triangle read by rows: T(n,k) is the number of skew Dyck paths of semilength n and having height of the first peak equal to k (1 <= k <= n).at n=46A128744
• Number of divisors d of n! such that d-1 is prime.at n=23A156190
• Generalized Riordan array based on the binomial transform of the Fine's numbers A000957.at n=46A187914
• Starting position of the first occurrence of a string of 2^n in the decimal expansion of Pi.at n=15A194351
• Triangle A106534 with reversed rows.at n=53A280470
• Partial sums of A299277.at n=34A299278
• Square array A(n,k), n >= 0, k >= 0, read by antidiagonals, where A(n,k) = Sum_{j=0..n} k^j * binomial(n,j) * Catalan(j+1).at n=53A386408