Number of nXnXn triangular 0..2 arrays with new values introduced in sequential zero-upwards order and exactly one inverted 2x2x2 triangle having values all different.
A271240
Number of nXnXn triangular 0..2 arrays with new values introduced in sequential zero-upwards order and exactly one inverted 2x2x2 triangle having values all different.
Terms
- a(0) =0a(1) =0a(2) =27a(3) =3969a(4) =900963a(5) =401227533a(6) =378139318893
External references
- oeis: A271240