1/6 the number of (n+2)X(n+2) 0..2 arrays with each 3X3 subblock containing one of one value, four of another, and four of the last.

A184468

1/6 the number of (n+2)X(n+2) 0..2 arrays with each 3X3 subblock containing one of one value, four of another, and four of the last.

Terms

    a(0) =315a(1) =2755a(2) =14119a(3) =53739a(4) =247879a(5) =904411a(6) =2909367

External references