Search: id:A080973
Results 1-1 of 1 results found.

%I A080973
%S A080973 2,52,14952,4007632,268874213792,68836555442592,4561331969745081152,
%T A080973 300550070677246403229312,1294530259719904904564091957759232,
%U A080973 331402554328705507772604330809117952
%N A080973 A014486-encoding of the "Moose trees".
%C A080973 Meeussen's observation about the orbits of a composition of two involutions 
               F and R states that if the orbit size of the composition (acting 
               on a particular element of the set) is odd, then it contains an element 
               fixed by the other involution if and only if it contains also an 
               element fixed by the other, on the (almost) opposite side of the 
               cycle. Here those two involutions are A057163 and A057164, their 
               composition is Donaghey's "Map M" A057505 and as the trees A080293/
               A080295 are symmetric as binary trees and the cycle sizes A080292 
               are odd, it follows that these are symmetric as general trees.
%H A080973 A. Karttunen, <a href="a080973.pdf">Initial terms illustrated</a>
%F A080973 a(n) = A014486(A080975(n)) = A014486(A057505^((A080292(n)+1)/2) (A080293(n))) 
               [where ^ stands for the repeated applications of permutation A057505.]
%Y A080973 Same sequence in binary: A080974. A036044(a(n)) = a(n) for all n. The 
               number of edges (as general trees): A080978.
%Y A080973 Sequence in context: A099882 A121293 A057106 this_sequence A079179 A000654 
               A061306
%Y A080973 Adjacent sequences: A080970 A080971 A080972 this_sequence A080974 A080975 
               A080976
%K A080973 nonn
%O A080973 0,1
%A A080973 Antti Karttunen (my_firstname.my_surname(AT)iki.fi) Mar 02 2003

Search completed in 0.001 seconds