Hilltop maps: number of nX4 binary arrays indicating the locations of corresponding elements not exceeded by any horizontal or vertical neighbor in a random 0..3 nX4 array.

A218192

Hilltop maps: number of nX4 binary arrays indicating the locations of corresponding elements not exceeded by any horizontal or vertical neighbor in a random 0..3 nX4 array.

Terms

    a(0) =15a(1) =251a(2) =4067a(3) =65251a(4) =1044001a(5) =16703113a(6) =267240217a(7) =4275711525a(8) =68409381991

External references