Array read by antidiagonals: T(n,k) is the number of (planar) unlabeled k-ary cacti having n polygons.
A303912
Array read by antidiagonals: T(n,k) is the number of (planar) unlabeled k-ary cacti having n polygons.
Terms
- a(0) =1a(1) =1a(2) =1a(3) =1a(4) =1a(5) =1a(6) =1a(7) =1a(8) =2a(9) =1a(10) =1a(11) =1a(12) =3a(13) =3a(14) =1a(15) =1a(16) =1a(17) =4a(18) =6a(19) =6a(20) =1a(21) =1a(22) =1a(23) =5a(24) =10a(25) =19a(26) =10a(27) =1a(28) =1a(29) =1
External references
- oeis: A303912