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A258428
Decimal expansion of arctan(1/e).
3
3, 5, 2, 5, 1, 3, 4, 2, 1, 7, 7, 7, 6, 1, 8, 9, 9, 7, 4, 7, 0, 8, 5, 9, 9, 2, 2, 7, 2, 3, 9, 5, 3, 5, 0, 0, 3, 5, 9, 4, 5, 2, 7, 5, 0, 2, 1, 9, 3, 9, 6, 4, 0, 5, 4, 3, 7, 8, 1, 2, 0, 3, 3, 2, 0, 5, 7, 2, 9, 9, 8, 6, 8, 4, 2, 3, 4, 3, 7, 3, 5, 5, 5, 2, 0, 4, 8, 2, 4, 4, 5, 1, 5, 2, 8, 6, 4, 0, 3, 2, 8, 8, 2, 1, 0
OFFSET
0,1
COMMENTS
The slope of the unique straight line passing through the origin which kisses the logarithmic function y=log(x), i.e., the angle (in radians) the tangent line subtends with the X axis. The kissing point coordinates are (e,1).
LINKS
FORMULA
Equals Integral_{x=1..oo} 1/(2*cosh(x)) dx. - Amiram Eldar, Aug 10 2020
EXAMPLE
0.35251342177761899747085992272395350035945275021939640543781203320...
In degrees:
20.1975312895726498111743461325943940876066625590453644638010046029...
MATHEMATICA
RealDigits[ArcTan[Exp[-1]], 10, 105][[1]] (* Vaclav Kotesovec, Jun 02 2015 *)
PROG
(PARI) atan(1/exp(1))
CROSSREFS
KEYWORD
nonn,cons
AUTHOR
Stanislav Sykora, May 31 2015
STATUS
approved