Number of n X n 0..4 arrays with rows and columns lexicographically nondecreasing and no element equal to the number of horizontal and vertical neighbors equal to itself.
A201721
Number of n X n 0..4 arrays with rows and columns lexicographically nondecreasing and no element equal to the number of horizontal and vertical neighbors equal to itself.
Terms
- a(0) =4a(1) =90a(2) =19827a(3) =56836178
External references
- oeis: A201721