Number of ways to reciprocally link elements of an 3 X n array either to themselves or to exactly one horizontal or antidiagonal neighbor.

A220564

Number of ways to reciprocally link elements of an 3 X n array either to themselves or to exactly one horizontal or antidiagonal neighbor.

Terms

    a(0) =1a(1) =13a(2) =64a(3) =430a(4) =2604a(5) =16310a(6) =101052a(7) =628269a(8) =3901815a(9) =24240377a(10) =150578968a(11) =935414825a(12) =5810847665a(13) =36097422853a(14) =224239670624

External references