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A078110
Decimal expansion of K210.
0
0, 0, 0, 0, 0, 0, 0, 0, 0, 5, 2, 0, 2, 5, 2, 4, 1, 8, 4, 7, 0, 6, 4, 5, 0, 4, 8, 0, 4, 8, 9, 8, 9, 9, 4, 6, 7, 5, 0, 7, 6, 0, 1, 4, 6, 7, 8, 7, 4, 8, 4, 4, 5, 1, 2, 2, 9, 2, 6, 5, 2, 2, 5, 9, 7, 0, 0, 3, 1, 3, 7, 0, 0, 2, 5, 4, 0, 0, 5, 5, 8, 0, 4, 6, 9, 6, 0, 7, 7, 7, 5, 3, 4, 6, 7, 7, 6, 6, 1, 2, 5, 0, 4, 8
OFFSET
0,10
COMMENTS
Related to modular functions and approximations to Pi : K210 is one of the most famous singular value calculated by Ramanujan. -2/sqrt(210)*log(K210/4) = 3.14159265358979323847198.. agrees with Pi to 20 decimal places
REFERENCES
L. Berggren, J. Borwein and P. Borwein, "Pi a source Book", second edition, Springer, p. 592
FORMULA
K210=(sqrt(2)-1)^2*(2-sqrt(3))*(sqrt(7)-sqrt(6))^2*(8-3*sqrt(7))*(sqrt(10)-3)^2*(sqrt(15)-sqrt(14))*(4-sqrt(15))^2*(6-sqrt(35))
EXAMPLE
0.0000000005202524184706450480489....
CROSSREFS
Sequence in context: A369286 A375694 A244813 * A334708 A201528 A093814
KEYWORD
cons,nonn
AUTHOR
Benoit Cloitre, Dec 03 2002
STATUS
approved