2023/04/16 by Panraksa, Chatchawan, Samart, Detchat, Sriwongsa, Songpon · 1 citation
#11C08 #11R04 #33B10 #37C25 #Dynamical Systems (math.DS) #FOS: Mathematics #Number Theory (math.NT)
paper · doi:10.48550/arxiv.2304.07823
Niven's theorem asserts that \cos(rπ) | r∈ ℚ\∩ ℚ=\0,± 1,± 1/2\. In this paper, we use elementary techniques and results from arithmetic dynamics to obtain an algorithm for classifying all values in the set \cos(rπ) | r∈ ℚ\∩ K, where K is an arbitrary number field.