Number of lower triangles of an n X n 0..4 array with no element greater than the number its nonzero horizontal and vertical neighbors.

A195951

Number of lower triangles of an n X n 0..4 array with no element greater than the number its nonzero horizontal and vertical neighbors.

Terms

    a(0) =1a(1) =5a(2) =162a(3) =19913a(4) =10408097a(5) =23663085157

External references