Number of n X n 0..3 arrays with rows and columns lexicographically nondecreasing read forwards and nonincreasing read backwards.
A201974
Number of n X n 0..3 arrays with rows and columns lexicographically nondecreasing read forwards and nonincreasing read backwards.
Terms
- a(0) =4a(1) =30a(2) =1372a(3) =408599a(4) =858105364
External references
- oeis: A201974