Number of 2Xn 0..1 arrays with no element equal to more than two of its horizontal, diagonal or antidiagonal neighbors, with the exception of exactly two elements, and with new values introduced in order 0 sequentially upwards.

A281564

Number of 2Xn 0..1 arrays with no element equal to more than two of its horizontal, diagonal or antidiagonal neighbors, with the exception of exactly two elements, and with new values introduced in order 0 sequentially upwards.

Terms

    a(0) =0a(1) =0a(2) =5a(3) =18a(4) =141a(5) =602a(6) =2180a(7) =7006a(8) =20979a(9) =59698a(10) =163635a(11) =435900a(12) =1135036a(13) =2901852a(14) =7307093a(15) =18167506a(16) =44683929a(17) =108886702a(18) =263208036a(19) =631773802a(20) =1507041943a(21) =3575151970a(22) =8439694735a(23) =19835439712a(24) =46433224508a(25) =108305733064a(26) =251797970649

External references