Triangle Read by rows: T(n,k) is the number of rooted ordered trees with n non-root nodes with non-root node labels in {1,..,k} such that all labels appear at least once in all groups of sibling nodes.
A385123
Triangle Read by rows: T(n,k) is the number of rooted ordered trees with n non-root nodes with non-root node labels in {1,..,k} such that all labels appear at least once in all groups of sibling nodes.
Terms
- a(0) =1a(1) =0a(2) =1a(3) =0a(4) =2a(5) =2a(6) =0a(7) =5a(8) =6a(9) =6a(10) =0a(11) =14a(12) =22a(13) =36a(14) =24a(15) =0a(16) =42a(17) =90a(18) =150a(19) =240a(20) =120a(21) =0a(22) =132a(23) =378a(24) =648a(25) =1560a(26) =1800a(27) =720a(28) =0a(29) =429
External references
- oeis: A385123