Number of nX4 arrays of permutations of 4 copies of 0..n-1 with every element equal to at least one horizontal or antidiagonal neighbor and the top left element equal to 0.
A267616
Number of nX4 arrays of permutations of 4 copies of 0..n-1 with every element equal to at least one horizontal or antidiagonal neighbor and the top left element equal to 0.
Terms
- a(0) =1a(1) =4a(2) =42a(3) =906a(4) =33120a(5) =1839720a(6) =144491760a(7) =15248903040
External references
- oeis: A267616