1/6 the number of (n+2)X4 0..2 arrays with each 3X3 subblock containing two of one value, three of another, and four of the last.
A184405
1/6 the number of (n+2)X4 0..2 arrays with each 3X3 subblock containing two of one value, three of another, and four of the last.
Terms
- a(0) =16140a(1) =326100a(2) =6361037a(3) =127484430a(4) =2555137939a(5) =51389641795
External references
- oeis: A184405