Number of lower triangles of an n X n 0..4 array with new values introduced in row major order 0..4 and no two horizontal or vertical neighbors of any element equal.
A194889
Number of lower triangles of an n X n 0..4 array with new values introduced in row major order 0..4 and no two horizontal or vertical neighbors of any element equal.
Terms
- a(0) =1a(1) =3a(2) =33a(3) =1620a(4) =136080a(5) =17962560a(6) =3751608960
External references
- oeis: A194889