OFFSET
1,1
REFERENCES
Steven R. Finch, Mathematical Constants, Cambridge University Press, 2003, Section 3.6 Sobolev Isoperimetric Constants, p. 221.
FORMULA
EXAMPLE
5.13878013260283423689422...
MATHEMATICA
digits = 103; theta = x /. FindRoot[Cos[x]*Cosh[x] == 1, {x, 5}, WorkingPrecision -> digits+10]; lambda = theta^4/Pi^4; RealDigits[lambda, 10, digits] // First
CROSSREFS
KEYWORD
AUTHOR
Jean-François Alcover, Jun 26 2014
STATUS
approved