Triangle read by rows: T(n,k) is the number of short bushes with n edges and k branchnodes (i.e., nodes of outdegree at least two). A short bush is an ordered tree with no nodes of outdegree 1.
A108263
Triangle read by rows: T(n,k) is the number of short bushes with n edges and k branchnodes (i.e., nodes of outdegree at least two). A short bush is an ordered tree with no nodes of outdegree 1.
Terms
- a(0) =1a(1) =0a(2) =0a(3) =1a(4) =0a(5) =1a(6) =0a(7) =1a(8) =2a(9) =0a(10) =1a(11) =5a(12) =0a(13) =1a(14) =9a(15) =5a(16) =0a(17) =1a(18) =14a(19) =21a(20) =0a(21) =1a(22) =20a(23) =56a(24) =14a(25) =0a(26) =1a(27) =27a(28) =120a(29) =84
External references
- oeis: A108263