Number of rooted ordered trees with node weights summing to n, where the root has weight 0, non-root node weights are in {1,2,3}, and no nodes have the same weight as their parent node.
A382096
Number of rooted ordered trees with node weights summing to n, where the root has weight 0, non-root node weights are in {1,2,3}, and no nodes have the same weight as their parent node.
Terms
- a(0) =1a(1) =1a(2) =2a(3) =6a(4) =15a(5) =39a(6) =110a(7) =308a(8) =869a(9) =2499a(10) =7238a(11) =21086a(12) =61871a(13) =182523a(14) =540830a(15) =1609238a(16) =4805871a(17) =14398559a(18) =43264896a(19) =130347450a(20) =393650751a(21) =1191441349a(22) =3613345360a(23) =10978726634a(24) =33414836743a(25) =101863289331a(26) =310984519412a(27) =950734751040
External references
- oeis: A382096