A019976 Decimal expansion of tangent of 78 degrees.

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

Offset

1,1

Comments

Also the decimal expansion of cotangent of 12 degrees. - Ivan Panchenko, Sep 01 2014

An algebraic integer of degree 8. - Charles R Greathouse IV, Nov 05 2017

Links

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

Wikipedia, Exact trigonometric constants

Index entries for algebraic numbers, degree 8

Formula

Equals A019887 / A019821 = A019833/(1-A019875) . - R. J. Mathar, Sep 06 2025

Minimal polynomial x^8 -28*x^6 +134*x^4 -92*x^2 +1. - R. J. Mathar, Jun 03 2026

Example

tan(13*Pi/30) = 4.704630109478454233586234537402900275699260747802...

Mathematica

First[RealDigits[Tan[78 Degree], 10, 100]] (* Paolo Xausa, Nov 16 2025 *)

Prog

(PARI) 1/tan(Pi/15) \\ Charles R Greathouse IV, Nov 05 2017

Crossrefs

Sequence in context: A023961 A147863 A358662 * A021072 A195791 A331790

Adjacent sequences: A019973 A019974 A019975 * A019977 A019978 A019979

Keyword

nonn,cons,easy

Author

N. J. A. Sloane

Status

approved