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A019973 Decimal expansion of tangent of 75 degrees. 7
3, 7, 3, 2, 0, 5, 0, 8, 0, 7, 5, 6, 8, 8, 7, 7, 2, 9, 3, 5, 2, 7, 4, 4, 6, 3, 4, 1, 5, 0, 5, 8, 7, 2, 3, 6, 6, 9, 4, 2, 8, 0, 5, 2, 5, 3, 8, 1, 0, 3, 8, 0, 6, 2, 8, 0, 5, 5, 8, 0, 6, 9, 7, 9, 4, 5, 1, 9, 3, 3, 0, 1, 6, 9, 0, 8, 8, 0, 0, 0, 3, 7, 0, 8, 1, 1, 4, 6, 1, 8, 6, 7, 5, 7, 2, 4, 8, 5, 7 (list; constant; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Also, 2 + sqrt(3) = cotangent of 15 degrees. - Rick L. Shepherd, Jul 04 2004

An equivalent definition of this sequence: decimal expansion of x > 1 satisfying x^2 - 4*x + 1 = 0. - Arkadiusz Wesolowski, Nov 28 2011

An algebraic integer of degree 2 with minimal polynomial x^2 - 4x + 1. - Charles R Greathouse IV, Oct 17 2016

LINKS

Ivan Panchenko, Table of n, a(n) for n = 1..1000

Wikipedia, Exact trigonometric constants

EXAMPLE

3.732050807568877293527446341505872366942805253810380628...

MATHEMATICA

RealDigits[Tan[75 Degree], 10, 120][[1]] (* Harvey P. Dale, Nov 08 2011 *)

PROG

(PARI) sqrt(3)+2 \\ Charles R Greathouse IV, Oct 17 2016

CROSSREFS

Cf. A002194 (sqrt(3)).

Sequence in context: A256978 A021272 A135613 * A010623 A066065 A145511

Adjacent sequences:  A019970 A019971 A019972 * A019974 A019975 A019976

KEYWORD

nonn,cons

AUTHOR

N. J. A. Sloane.

EXTENSIONS

Checked by Neven Juric (neven.juric(AT)apis-it.hr), Feb 04 2008

STATUS

approved

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Last modified December 8 02:07 EST 2016. Contains 278902 sequences.