Number of incongruental unlabeled undirected trees with n nodes on a square lattice and edges of length 1 or sqrt(2) admitted to the 4 nearest or 4 2nd nearest neighbors.
A056787
Number of incongruental unlabeled undirected trees with n nodes on a square lattice and edges of length 1 or sqrt(2) admitted to the 4 nearest or 4 2nd nearest neighbors.
Terms
- a(0) =1a(1) =2a(2) =6a(3) =40a(4) =303a(5) =2929a(6) =29752a(7) =316935
External references
- oeis: A056787