Number of n X 4 0..1 arrays with every 1 horizontally or antidiagonally adjacent to 1 neighboring 1s.

A297220

Number of n X 4 0..1 arrays with every 1 horizontally or antidiagonally adjacent to 1 neighboring 1s.

Terms

    a(0) =4a(1) =16a(2) =57a(3) =207a(4) =751a(5) =2720a(6) =9861a(7) =35741a(8) =129540a(9) =469528a(10) =1701805a(11) =6168220a(12) =22356839a(13) =81032722a(14) =293704534a(15) =1064537220a(16) =3858433620a(17) =13984959985a(18) =50688731051a(19) =183722188635a(20) =665904273716

External references