cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A285660 Degree of the algebraic number sin(n degrees) = sin(n Pi/180 radians).

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%I A285660 #7 Oct 13 2022 13:58:45
%S A285660 1,48,12,16,24,12,4,48,24,8,3,48,8,48,12,4,24,48,2,48,6,16,12,48,8,12,
%T A285660 12,8,24,48,1,48,24,16,12,12,4,48,12,16,6,48,4,48,24,2,12,48,8,48,3,
%U A285660 16,24,48,2,12,24,16,12,48,2,48,12,8,24,12,4,48,24,16,3,48,4,48,12,4,24,48,4,48,6,8,12,48,8,12,12,16,24,48,1
%N A285660 Degree of the algebraic number sin(n degrees) = sin(n Pi/180 radians).
%C A285660 By definition, a(n) is the degree of the minimal polynomial of sin(n degrees).
%C A285660 Periodic sequence of period 360.
%C A285660 The sequence range is the set of all divisors of 48 (A018261), where 48 = Euler_phi(180) = A000010(180).
%C A285660 All 48 distinct algebraic numbers of degree 48 referenced here (i.e., where GCD(n, 180) = 1) have the same minimal polynomial, which is shown in A019810.
%H A285660 <a href="/index/Rec#order_180">Index entries for linear recurrences with constant coefficients</a>, order 180.
%F A285660 a(n) = a(n-360) for all n (extending the sequence to negative n).
%e A285660 sin(6 degrees) has minimal polynomial 16x^4 + 8x^3 - 16x^2 - 8x + 1 of degree 4, so a(6) = 4. sin(15 degrees) also has a minimal polynomial of degree 4 (but a different one, 16x^4 - 16x^2 + 1), so a(15) = 4.
%Y A285660 Cf. A019810 (sin(1 degree)), A018261 (divisors of 48), A007775.
%K A285660 nonn,easy
%O A285660 0,2
%A A285660 _Rick L. Shepherd_, Apr 23 2017