1/4 the number of n X n 0..3 arrays with no element equal both to the element above and to the element to its left.
A185560
1/4 the number of n X n 0..3 arrays with no element equal both to the element above and to the element to its left.
Terms
- a(0) =1a(1) =60a(2) =50580a(3) =598507920
External references
- oeis: A185560