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Template:Sequence of the Day for October 17

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Intended for: October 17, 2012

Timetable

  • First draft entered by Alonso del Arte on April 8, 2012
  • Draft reviewed by Daniel Forgues on October 16, 2012
  • Draft to be approved by September 17, 2012
Yesterday's SOTD * Tomorrow's SOTD

The line below marks the end of the <noinclude> ... </noinclude> section.



A019973: Decimal expansion of tangent of 75° (
5 π
12
radians), or of cotangent of 15° (
π
12
radians).
3.732050807568877...
This number
c = 2 +
2  3
, one of the two roots of
x 2  −  4 x + 1 = 0
, is connected to the Lucas–Lehmer sequence via the formula
a (n)  =  c  +  (2n  ) + c  −  (2n  ).