856900

Appears in sequences

• The number of lit cells in weakly increasing partitions of n when light shines from the northwest. Here partitions are represented from left to right by columns of cells.at n=40A366069
• a(n) = Sum_{k=0..n} 4^(n-k) * binomial(n+k-1,k) * binomial(k/2,n-k).at n=9A378554