Triangle read by rows: T(n,k) is the number of ternary trees with n edges and having k vertices of outdegree 2 (n >= 0, k >= 0).
A120982
Triangle read by rows: T(n,k) is the number of ternary trees with n edges and having k vertices of outdegree 2 (n >= 0, k >= 0).
Terms
- a(0) =1a(1) =3a(2) =9a(3) =3a(4) =28a(5) =27a(6) =93a(7) =162a(8) =18a(9) =333a(10) =825a(11) =270a(12) =1272a(13) =3915a(14) =2430a(15) =135a(16) =5085a(17) =18144a(18) =17199a(19) =2835a(20) =20925a(21) =84000a(22) =106596a(23) =34020a(24) =1134a(25) =87735a(26) =391554a(27) =612360a(28) =308448a(29) =30618
External references
- oeis: A120982