1/9 the number of triangular nXnXn arrays of integers in 1..9 with no element or any of its neighbors having the same value.
A180372
1/9 the number of triangular nXnXn arrays of integers in 1..9 with no element or any of its neighbors having the same value.
Terms
- a(0) =1a(1) =56a(2) =6720a(3) =1290240a(4) =392232960
External references
- oeis: A180372