Number of (s(0), s(1), ..., s(2n)) such that 0 < s(i) < 8 and |s(i) - s(i-1)| = 1 for i = 1,2,...,2n, s(0) = 1, s(2n) = 5.

A094806

Number of (s(0), s(1), ..., s(2n)) such that 0 < s(i) < 8 and |s(i) - s(i-1)| = 1 for i = 1,2,...,2n, s(0) = 1, s(2n) = 5.

Terms

    a(0) =1a(1) =5a(2) =20a(3) =74a(4) =264a(5) =924a(6) =3200a(7) =11016a(8) =37792a(9) =129392a(10) =442496a(11) =1512224a(12) =5165952a(13) =17643456a(14) =60250112a(15) =205729920a(16) =702452224a(17) =2398414592a(18) =8188884992a(19) =27958972928a(20) =95458646016a(21) =325917686784

External references