cp's OEIS Frontend

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).

%I A079218 #6 Mar 31 2012 14:02:26
%S A079218 1,1,1,2,2,1,5,5,0,1,11,14,0,0,1,26,36,1,2,0,1,66,94,0,0,0,0,1,161,
%T A079218 253,0,5,0,0,0,1,420,668,2,0,0,2,0,0,1,1093,1807,0,14,1,0,0,0,0,1,
%U A079218 2916,4902,0,0,0,0,0,0,0,0,1,7819,13436,5,36,0,5,0,2,0,0,0,1,21304,37016,0,0,0,0
%N 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).
%C A079218 Note: the counts given here are inclusive, i.e. T(n,d) includes also the count A079217(n,d).
%p A079218 [seq(A079218(n),n=0..119)]; A079218 := n -> PFixedByA057511(A003056(n)+1,2, A002262(n)+1);
%Y A079218 The row sums equal to the left edge shifted left once = A079223 = second row of A079216 (the latter gives the Maple procedure PFixedByA057511). Cf. also A079217-A079222 and A003056 & A002262.
%K A079218 nonn,tabl
%O A079218 0,4
%A A079218 _Antti Karttunen_ Jan 03 2002