Number of unordered sets of pairs (in-degree, out-degree) for nodes of directed trees on n unlabeled nodes (the edges are directed in arbitrary directions, the tree is unrooted).
A007835
Number of unordered sets of pairs (in-degree, out-degree) for nodes of directed trees on n unlabeled nodes (the edges are directed in arbitrary directions, the tree is unrooted).
Terms
- a(0) =1a(1) =1a(2) =3a(3) =8a(4) =21a(5) =52a(6) =124a(7) =284a(8) =629a(9) =1352a(10) =2829a(11) =5777a(12) =11544
External references
- oeis: A007835