Minimal polynomials of algebraic cosine values at rational multiples of \(\pi \)
Journal of integer sequences, Tome 19 (2016) no. 2
Lehmer proved that the values of the cosine function evaluated at rational multiples of $\pi $ are algebraic numbers. We show how to determine explicit, closed form expressions for the minimal polynomials of these algebraic numbers.
Classification : 11R04, 33B10, 11J72
Keywords: cosine function, algebraic value, multiple of pi
@article{JIS_2016__19_2_a7,
     author = {Tangsupphathawat,  Pinthira and Laohakosol,  Vichian},
     title = {Minimal polynomials of algebraic cosine values at rational multiples of \(\pi \)},
     journal = {Journal of integer sequences},
     year = {2016},
     volume = {19},
     number = {2},
     zbl = {1344.11068},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/JIS_2016__19_2_a7/}
}
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Tangsupphathawat,  Pinthira; Laohakosol,  Vichian. Minimal polynomials of algebraic cosine values at rational multiples of \(\pi \). Journal of integer sequences, Tome 19 (2016) no. 2. http://geodesic.mathdoc.fr/item/JIS_2016__19_2_a7/