1/36 the number of (n+2) X (n+2) 0..2 arrays with each 3 X 3 subblock containing two of one value, two of another, and five of the last.
A184448
1/36 the number of (n+2) X (n+2) 0..2 arrays with each 3 X 3 subblock containing two of one value, two of another, and five of the last.
Terms
- a(0) =63a(1) =600a(2) =3125a(3) =11766a(4) =53350a(5) =196974a(6) =660654
External references
- oeis: A184448