OFFSET
1,1
COMMENTS
The quadratic form to maximize is (sum_(k>=1) x(k)/k)^2 + sum_(k>=1) (x(k)/k)^2, subject to the constraint (sum_(k>=1) x(k)^2) <= 1.
REFERENCES
Steven R. Finch, Mathematical Constants, Cambridge University Press, 2003, Section 3.12 Du Bois Reymond's constants, p. 239.
FORMULA
(Pi/xi)^2, where xi is the smallest positive solution of the equation x+tan(x)=0.
EXAMPLE
2.397945586114436337406139378906...
MATHEMATICA
xi = x /. FindRoot[x + Tan[x] == 0, {x, 2}, WorkingPrecision -> 100]; RealDigits[(Pi/xi)^2] // First
CROSSREFS
KEYWORD
AUTHOR
Jean-François Alcover, Jun 24 2014
STATUS
approved