OFFSET
1,2
COMMENTS
A grove of degree n is a nonempty subset of the set of binary trees of degree n.
The next term a(7) has 130 decimal digits. - Andrew Howroyd, Oct 05 2023
LINKS
Andrew Howroyd, Table of n, a(n) for n = 1..8
Adriano Bruno and Dan Yasaki, The arithmetic of trees, arXiv:0809.4448 [math.CO]. See Table 1.
J.-L. Loday, Arithmetree, J. Algebra 258 (2002), no. 1, 275-309.
FORMULA
a(n) = 2^A000108(n) - 1. - Andrey Zabolotskiy, Oct 05 2023
CROSSREFS
KEYWORD
nonn
AUTHOR
Jonathan Vos Post, Sep 27 2008
STATUS
approved