Number of nX2 arrays containing 2 copies of 0..n-1 with every element equal to or 1 greater than any west neighbor modulo n and the upper left element equal to 0.

A267625

Number of nX2 arrays containing 2 copies of 0..n-1 with every element equal to or 1 greater than any west neighbor modulo n and the upper left element equal to 0.

Terms

    a(0) =1a(1) =3a(2) =7a(3) =27a(4) =138a(5) =900a(6) =7110a(7) =66150a(8) =708120a(9) =8573040a(10) =115781400a(11) =1725154200a(12) =28103922000a(13) =496799503200

External references