The number of walks from (0,0,0,0) to (n,n,n,n) with steps that increment one to four coordinates and having the property that no two consecutive steps are orthogonal.

A171563

The number of walks from (0,0,0,0) to (n,n,n,n) with steps that increment one to four coordinates and having the property that no two consecutive steps are orthogonal.

Terms

    a(0) =1a(1) =1a(2) =183a(3) =12645a(4) =985035a(5) =81827267a(6) =7118644591a(7) =640769321689

External references