Triangle T(n,d) (listed row-wise: T(1,1)=1, T(2,1)=1, T(2,2)=1, T(3,1)=2, T(3,2)=2, T(3,3)=1, ...) giving the number of n-edge general plane trees with root degree d that are fixed by the two-fold application of Catalan Automorphisms A057511/A057512 (Deep rotation of general parenthesizations/plane trees).

A079218

Triangle T(n,d) (listed row-wise: T(1,1)=1, T(2,1)=1, T(2,2)=1, T(3,1)=2, T(3,2)=2, T(3,3)=1, ...) giving the number of n-edge general plane trees with root degree d that are fixed by the two-fold application of Catalan Automorphisms A057511/A057512 (Deep rotation of general parenthesizations/plane trees).

Terms

    a(0) =1a(1) =1a(2) =1a(3) =2a(4) =2a(5) =1a(6) =5a(7) =5a(8) =0a(9) =1a(10) =11a(11) =14a(12) =0a(13) =0a(14) =1a(15) =26a(16) =36a(17) =1a(18) =2a(19) =0a(20) =1a(21) =66a(22) =94a(23) =0a(24) =0a(25) =0a(26) =0a(27) =1a(28) =161a(29) =253

External references