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A051496
Decimal expansion of the probability that a point of an infinite (rooted) tree is fixed by every automorphism of the tree.
0
6, 9, 9, 5, 3, 8, 8, 7, 0, 0, 6, 0, 9, 8, 9, 2, 3, 3, 2, 1, 6, 6, 3, 1, 2, 1, 8, 6, 2, 0, 1, 4, 2, 7, 6, 7, 1, 6, 3, 6, 8, 1, 4, 5, 5, 4, 6, 3, 5, 4, 2, 1, 6, 1, 9, 8, 9, 7, 5, 9, 2, 2, 0, 3, 2, 0, 0, 4, 6, 4, 1, 9, 2, 5, 6, 2, 9, 5, 6, 1, 2, 1, 4, 8, 7, 8, 4, 8, 0, 6, 0, 2, 8, 2, 6, 5, 4, 8
OFFSET
0,1
COMMENTS
F. Harary and E. M. Palmer derive certain functional equations and, using the methods of G. Polya (Acta Math. (1937) Vol. 68, 145-254) and R. Otter (Ann. of Math. (2) 49 (1948), 583-599; Math. Rev. 10, 53), prove that the limiting probability of a fixed point in a large random tree, whether rooted or not, is 0.6995...
REFERENCES
Steven R. Finch, Mathematical Constants, Encyclopedia of Mathematics and its Applications, vol. 94, Cambridge University Press, 2003, Section 5.6.3, p. 304.
LINKS
D. J. Broadhurst and D. Kreimer, Renormalization automated by Hopf algebra, arXiv:hep-th/9810087, 1998.
Frank Harary and Edgar M. Palmer, The probability that a point of a tree is fixed, Math. Proc. Cambridge Philos. Soc. 85 (1979), no. 3, 407-415.
FORMULA
Equals lim_{n->oo} A005200(n)/(n*A000081(n)).
Equals lim_{n->oo} A005201(n)/(n*A000055(n)).
EXAMPLE
0.6995388700609892332166312186...
CROSSREFS
KEYWORD
nonn,cons
STATUS
approved