Sum of neighbor maps: number of n X 2 binary arrays indicating the locations of corresponding elements equal to the sum mod 4 of their king-move neighbors in a random 0..3 n X 2 array.

A221066

Sum of neighbor maps: number of n X 2 binary arrays indicating the locations of corresponding elements equal to the sum mod 4 of their king-move neighbors in a random 0..3 n X 2 array.