A086317 Decimal expansion of asymptotic constant xi for counts of weakly binary trees.

2, 4, 8, 3, 2, 5, 3, 5, 3, 6, 1, 7, 2, 6, 3, 6, 8, 5, 8, 5, 6, 2, 2, 8, 8, 5, 1, 8, 1, 7, 8, 2, 2, 1, 2, 8, 9, 1, 8, 8, 6, 9, 7, 3, 4, 0, 8, 1, 4, 3, 6, 4, 5, 8, 5, 9, 2, 0, 2, 5, 9, 6, 9, 7, 3, 0, 6, 7, 4, 2, 5, 4, 0, 8, 8, 5, 8, 0, 9, 8, 3, 9, 0, 6, 4, 7, 6, 4, 0, 1, 6, 9, 1, 6, 7, 2, 1, 8, 2, 7, 4, 7

Offset

1,1

Links

Vincenzo Librandi, Table of n, a(n) for n = 1..1000

Lyuben Lichev, Dieter Mitsche, On the modularity of 3-regular random graphs and random graphs with given degree sequences, arXiv:2007.15574 [math.PR], 2020.

Eric Weisstein's World of Mathematics, Weakly binary tree

Formula

Equals 1/A240943.

Equals lim_{n->infinity} A001190(n)^(1/n). - Vaclav Kotesovec, Jul 28 2014

Example

2.48325353617263685856228851817822128918869734...

Mathematica

digits = 102; c[0] = 2; c[n_] := c[n] = c[n - 1]^2 + 2; xi[n_Integer] := xi[n] = c[n]^(2^-n); xi[5]; xi[n = 10]; While[RealDigits[xi[n], 10, digits] != RealDigits[xi[n - 5], 10, digits], n = n + 5]; RealDigits[xi[n], 10, digits] // First (* Jean-François Alcover, May 27 2014 *)

Crossrefs

Cf. A001190, A086318, A240943.

Cf. A000672, A003214.

Sequence in context: A263410 A344915 A285334 * A356693 A110217 A338196

Adjacent sequences: A086314 A086315 A086316 * A086318 A086319 A086320

Keyword

nonn,cons

Author

Eric W. Weisstein, Jul 15 2003

Extensions

Typos corrected by Jean-François Alcover, May 27 2014

Status

approved