Equals two maps: number of nX4 binary arrays indicating the locations of corresponding elements equal to exactly two of their horizontal, vertical and antidiagonal neighbors in a random 0..2 nX4 array.
A221187
Equals two maps: number of nX4 binary arrays indicating the locations of corresponding elements equal to exactly two of their horizontal, vertical and antidiagonal neighbors in a random 0..2 nX4 array.
Terms
- a(0) =4a(1) =107a(2) =2648a(3) =51924a(4) =928133a(5) =15638551a(6) =256020803
External references
- oeis: A221187