48840

Appears in sequences

• Number of polyominoes of 2n-1 cells that span an n X n square.at n=9A057051
• Number of 4 X n (0,1) matrices such that each row and each column is nondecreasing or nonincreasing.at n=14A086114
• Numbers whose number of divisors equals the sum of their separate prime-power decompositions.at n=19A087004
• a(n) = rightmost term in M^n * [1 0 0]. M = the 3 X 3 stiffness matrix [1 -1 0 / -1 4 -3 / 0 -3 3].at n=6A094432
• Number of acute triangles, distinct up to congruence, on an n X n grid (or geoboard).at n=30A190021
• Number of n X 7 0..1 arrays avoiding 0 0 0 and 1 1 1 horizontally and 0 0 1 and 0 1 1 vertically.at n=4A208068
• Number of 5 X n 0..1 arrays avoiding 0 0 0 and 1 1 1 horizontally and 0 0 1 and 0 1 1 vertically.at n=6A208070
• Integer areas A of integer-sided cyclic quadrilaterals such that the length of the circumradius is a perfect square.at n=10A233315
• Square rings obtained by adding four identical cuboids from A169938, a(n) = 4*n*(n+1)*(n*(n+1)+1).at n=10A288486
• Number of dying nodes (withering branches) at generation n in the binary tree of persistently squarefree numbers (A293230).at n=43A293520
• Take apart the sides of each of the integer-sided triangles with perimeter n (at their vertices) and rearrange them orthogonally in 3-space so that their endpoints coincide at a single point. a(n) is the total surface area of all rectangular prisms enclosed in this way.at n=43A308236
• Numbers that are the average of more pairs of distinct twin primes than any previous number.at n=37A335992
• Triangle T(n,m) = Sum_{i=0..n-m} C(2*m-1,n-i-1)*C(n-i-1,i)*C(n-i-1,n-m-i)/(2*m-1).at n=51A338022
• a(n) is the smallest number that has exactly n repdigit divisors.at n=18A355699
• Consecutive states of the linear congruential pseudo-random number generator (3661*s + 30809) mod 145800 when started at s=1.at n=31A385365