24780

Appears in sequences

• Number of n-step self-avoiding walks on f.c.c. lattice ending at point with x = 1.at n=4A000766
• Numerator of n*(n-2)*(2*n-1)/(2*(n-1)).at n=28A022997
• Numbers k such that 5*2^k + 3 is prime.at n=52A058586
• a(n) = 36*n^2 - 55*n + 21.at n=26A157262
• Number of ways to place 2 nonattacking wazirs on an n X n board.at n=14A172225
• Molecular topological indices of the crown graphs.at n=14A192796
• Numbers n such that n!8-1 is prime.at n=61A204662
• Triangle T(n,k) represents the coefficients of (x^12*d/dx)^n, where n>=1; generalization of Stirling numbers of second kind A008277, Lah-numbers A008297.at n=25A223514
• Triangle read by rows: Number of n-step self-avoiding walks on f.c.c. lattice ending at point with x = k.at n=16A227511
• Triangular array read by rows. T(n,k) is the number of n-permutations with k cycles of length one or k cycles of length two, n>=0,0<=k<=n.at n=48A237928
• a(n) = sigma(n)*pi(n^2), where sigma(n) is the sum of all (positive) divisors of n, and pi(x) is the number of primes not exceeding x.at n=43A263325
• Numbers k such that the largest prime divisor of k^4+1 is less than k.at n=29A309562
• Regular triangle read by rows where T(n,k) is the number of set partitions of {1,...,n} with k topologically connected components.at n=59A324173
• Table read by antidiagonals: Place k points in general position on each side of a regular n-gon and join every pair of the n*(k+1) boundary points by a chord; T(n,k) (n >= 3, k >= 0) gives number of regions in the resulting planar graph.at n=31A366253
• a(n) = Sum_{k=0..floor(n/3)} binomial(k+3,3) * binomial(k,n-3*k)^2.at n=22A377150
• Triangle read by rows: T(n,k) = number of heapable permutations of length n with exactly k decreasing runs.at n=59A389255
• Triangle read by rows: T(n,k) = number of heapable permutations of length n with exactly k increasing runs.at n=61A389487