OFFSET
0,1
LINKS
Eric Weisstein's World of Mathematics, Yff Conjecture
EXAMPLE
0.44005346705249230239...
MATHEMATICA
f[a_] := a^2*(Pi - 2*a) - 8*ArcCot[2*Cot[a] - Cot[2*a]]^3; a0 = a /. FindRoot[f'[a] == 0, {a, 3/2}, WorkingPrecision -> 110]; RealDigits[f[a0], 10, 105] // First (* Jean-François Alcover, Feb 07 2013, after Eric W. Weisstein *)
CROSSREFS
KEYWORD
nonn,cons
AUTHOR
Eric W. Weisstein, Sep 26 2007
STATUS
approved