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A120683 Decimal expansion of secant of 15 degrees (cosecant of 75 degrees). 5
1, 0, 3, 5, 2, 7, 6, 1, 8, 0, 4, 1, 0, 0, 8, 3, 0, 4, 9, 3, 9, 5, 5, 9, 5, 3, 5, 0, 4, 9, 6, 1, 9, 3, 3, 1, 3, 3, 9, 6, 2, 7, 5, 6, 0, 5, 2, 7, 9, 7, 2, 2, 0, 5, 5, 2, 5, 6, 0, 1, 2, 8, 2, 9, 2, 6, 0, 2, 2, 7, 8, 9, 8, 9, 9, 5, 2, 0, 7, 9, 8, 7, 6, 8, 9, 4, 7, 1, 8, 9, 8, 7, 7, 6, 9, 9, 8, 6, 6, 2, 0, 8, 3, 5, 8 (list; constant; graph; refs; listen; history; text; internal format)
OFFSET

1,3

COMMENTS

Side length of the largest equilateral triangle that can be inscribed in a unit square (as stated in MathWorld/Weisstein link).

A quartic integer. - Charles R Greathouse IV, Aug 27 2017

LINKS

Table of n, a(n) for n=1..105.

Eric Weisstein's World of Mathematics, Equilateral Triangle.

FORMULA

a(n) = sec(Pi/12) = sec(A019679) = sqrt(6) - sqrt(2) = A010464-A002193 = csc(5*Pi/12) = 1/sin(5*Pi/12) = 1/sin(10*A019691) = 1/A019884.

EXAMPLE

1.03527618041008304939559535049...

MATHEMATICA

RealDigits[Sec[15 Degree], 10, 120][[1]] (* Harvey P. Dale, Jun 03 2015 *)

PROG

(PARI) sqrt(6) - sqrt(2) \\ Charles R Greathouse IV, Aug 27 2017

CROSSREFS

Cf. A019679, A019691, A019884, A010464, A002193.

Sequence in context: A285297 A097465 A340272 * A210042 A338872 A274421

Adjacent sequences:  A120680 A120681 A120682 * A120684 A120685 A120686

KEYWORD

cons,nonn

AUTHOR

Rick L. Shepherd, Jun 24 2006

STATUS

approved

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Last modified November 28 13:39 EST 2021. Contains 349412 sequences. (Running on oeis4.)