Number of n X n 0..2 arrays with rows and columns lexicographically nondecreasing read forwards and nonincreasing read backwards.
A201694
Number of n X n 0..2 arrays with rows and columns lexicographically nondecreasing read forwards and nonincreasing read backwards.
Terms
- a(0) =3a(1) =10a(2) =116a(3) =4998a(4) =930564a(5) =795339012
External references
- oeis: A201694