%I A144964
%S A144964 1,3,31,16383,4398046511103,5444517870735015415413993718908291383295
%N A144964 Number of groves of degree n.
%C A144964 Let Y_n be the set of trees of degree n. A nonempty subset of Y_n is 
               called a
%C A144964 grove. The set of all groves of degree n is denoted by Y_n.
%C A144964 a(n) for n<= 7 given by right-most column of Table 1,
%C A144964 p.3, of Bruno and Yasaki: The arithmetic of the natural numbers N can 
               be extended
%C A144964 to arithmetic operations on planar binary trees. This gives rise to a
%C A144964 non-commutative arithmetic theory. In this exposition, we describe this
%C A144964 arithmetree, first defined by Loday and investigate prime trees.
%D A144964 J.-L. Loday, Arithmetree, J. Algebra 258 (2002), no. 1, 275-309, Special 
               issue in celebration of Claudio Procesi's 60th birthday.
%H A144964 Adriano Bruno, Dan Yasaki, <a href="http://arxiv.org/PS_cache/arxiv/pdf/
               0809/0809.4448v1.pdf">The arithmetic of trees</a>, Sep 25, 2008.
%Y A144964 Cf. A000108.
%Y A144964 Sequence in context: A129209 A134721 A002707 this_sequence A118913 A005042 
               A136582
%Y A144964 Adjacent sequences: A144961 A144962 A144963 this_sequence A144965 A144966 
               A144967
%K A144964 nonn
%O A144964 1,2
%A A144964 Jonathan Vos Post (jvospost3(AT)gmail.com), Sep 27 2008