268568

Appears in sequences

• Number of n element 0..2 arrays with each element the minimum of 5 adjacent elements of a random 0..2 array of n+4 elements.at n=18A217880
• a(n) = Sum_{k = 0..n} (-1)^k * binomial(n,k) * binomial(2*n,k).at n=14A234839