Number of (s(0), s(1), ..., s(2n)) such that 0 < s(i) < 9 and |s(i) - s(i-1)| = 1 for i = 1,2,...,2n, s(0) = 3, s(2n) = 5.

A094833

Number of (s(0), s(1), ..., s(2n)) such that 0 < s(i) < 9 and |s(i) - s(i-1)| = 1 for i = 1,2,...,2n, s(0) = 3, s(2n) = 5.

Terms

    a(0) =1a(1) =4a(2) =15a(3) =55a(4) =199a(5) =714a(6) =2548a(7) =9061a(8) =32148a(9) =113887a(10) =403051a(11) =1425471a(12) =5039254a(13) =17809336a(14) =62928201a(15) =222324436a(16) =785402143a(17) =2774421135a(18) =9800231959a(19) =34617003682a(20) =122274355596a(21) =431893332397

External references