OFFSET
2,5
COMMENTS
This constant is Heuberger and Wagner's lambda. They consider the number of maximum matchings a tree of n vertices may have, and show that the largest number of maximum matchings (A333347) grows as O(lambda^(n/7)) (see A333346 for the 7th root). Lambda is the larger eigenvalue of matrix M = [8,3/5,3] which is raised to a power when counting matchings in a chain of "C" parts in the trees (their lemma 6.2).
Apart from the first digit the same as A176522. - R. J. Mathar, Apr 03 2020
LINKS
Clemens Heuberger and Stephan Wagner, The Number of Maximum Matchings in a Tree, Discrete Mathematics, volume 311, issue 21, November 2011, pages 2512-2542; arXiv preprint, arXiv:1011.6554 [math.CO], 2010.
FORMULA
Equals continued fraction [10; 9] = 10 + 1/(9 + 1/(9 + 1/(9 + 1/...))). - Peter Luschny, Mar 15 2020
EXAMPLE
10.1097722286...
MATHEMATICA
With[{$MaxExtraPrecision = 1000}, First@ RealDigits[(11 + Sqrt[85])/2, 10, 105]] (* Michael De Vlieger, Mar 15 2020 *)
PROG
(PARI) (11 + sqrt(85))/2 \\ Michel Marcus, May 21 2020
CROSSREFS
KEYWORD
cons,nonn
AUTHOR
Kevin Ryde, Mar 15 2020
STATUS
approved