OFFSET
0,3
LINKS
Joerg Arndt, Arctan relations for Pi
Eric Weisstein's World of Mathematics, Machin-Like Formulas
Index entries for linear recurrences with constant coefficients, signature (0, 0, 0, 0, 0, 0, 1).
FORMULA
From Jean-François Alcover, Sep 14 2015: (Start)
Pi = 16 arctan(1/5) - 4 arctan(1/239) [Machin's formula],
arctan(1/239) = arctan(1/70) - arctan(1/99) = arctan(1/408) + arctan(1/577),
1/239 = 4649 / 1111111. (End)
CROSSREFS
KEYWORD
nonn,cons
AUTHOR
STATUS
approved