OFFSET
1,2
REFERENCES
Steven R. Finch, Mathematical Constants, Cambridge University Press, 2003, Section 3.6 Sobolev Isoperimetric Constants.
LINKS
David W. Boyd, Best constants in a class of integral inequalities, Pacific J. Math. Volume 30, Number 2 (1969), 367-383
Steven R. Finch, Errata and Addenda to Mathematical Constants, p. 31.
FORMULA
L = sqrt(3/2]*arctanh(sqrt(2/3)).
K = A246859 = 2/(L+1)^2.
EXAMPLE
1.40382196515535516573036373889961027748003532830665702207...
MATHEMATICA
RealDigits[Sqrt[3/2]*ArcTanh[Sqrt[2/3]], 10, 101] // First
CROSSREFS
KEYWORD
AUTHOR
Jean-François Alcover, Oct 16 2014
STATUS
approved