A019955 Decimal expansion of tangent of 57 degrees.

1, 5, 3, 9, 8, 6, 4, 9, 6, 3, 8, 1, 4, 5, 8, 2, 9, 0, 4, 8, 2, 6, 7, 9, 6, 9, 7, 2, 6, 0, 2, 7, 8, 0, 1, 2, 5, 7, 0, 8, 3, 8, 7, 0, 3, 2, 1, 6, 5, 4, 8, 1, 6, 7, 9, 7, 9, 9, 1, 8, 5, 5, 0, 3, 0, 0, 2, 3, 3, 3, 5, 6, 6, 9, 4, 9, 0, 8, 4, 1, 2, 5, 4, 0, 8, 1, 5, 7, 6, 6, 3, 6, 7, 8, 2, 9, 6, 5, 5

Offset: 1

Author

N. J. A. Sloane

Keywords

• nonn
• cons

Comments

Also the decimal expansion of cotangent of 33 degrees. - Ivan Panchenko, Sep 01 2014

Examples

			1.5398649638145829048267969726027801257083870321654816797991855...
		

Links

• Ivan Panchenko, Table of n, a(n) for n = 1..1000
• Wikipedia, Exact trigonometric constants

Crossrefs

Cf. A019866 (sine of 56 degrees).

Programs

Magma

SetDefaultRealField(RealField(100)); R:= RealField(); Tan(19*Pi(R)/60); // G. C. Greubel, Nov 22 2018

Mathematica

RealDigits[Tan[57 Degree],10,120][[1]] (* Harvey P. Dale, Jul 20 2016 *)
RealDigits[Tan[19*Pi/60], 10, 100][[1]] (* G. C. Greubel, Nov 22 2018 *)

PARI

default(realprecision, 100); tan(19*Pi/60) \\ G. C. Greubel, Nov 22 2018

Sage

numerical_approx(tan(19*pi/60), digits=100) # G. C. Greubel, Nov 22 2018

Formula

Equals cot(11*Pi/90) = (1/4)*(2 - sqrt(2*(5 - sqrt(5))))*(2 - (2 + sqrt(3))*(3 + sqrt(5))). - G. C. Greubel, Nov 22 2018