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.
%I A232627 #10 Feb 25 2025 01:45:59 %S A232627 1,1,12,1,2000,12,1075648,8,1259712,2000,2414538435584,1, %T A232627 7340688973975552,1075648,324000000,2048,187591757103747287810048, %U A232627 1259712,1436650532447139184230793216,5,843466573910016,2414538435584 %N A232627 Discriminants of the minimal polynomials of 2*sin(2*Pi/n) for n >= 1. %C A232627 The coefficient list for the minimal polynomials of 2*sin(2*Pi/n), called here MP(1; n, x), is given as A231188. %H A232627 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/PolynomialDiscriminant.html">Polynomial Discriminant</a>. %H A232627 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/VandermondeDeterminant.html">Vandermonde Determinant</a>. %F A232627 a(n) = discriminant of MP(1; n, x) = sum(A231188(n,m)*x^m, m=0..deg(1; n)) with the degree deg(1; n) = A093819(n), n >= 1. %e A232627 n=5: MP(1; 5, x) = 5 - 5*x^2 + x^4 with the four zeros x[1] = +sqrt(2 + tau), x[2] = -sqrt(2 + tau), x[3] = +sqrt(3 - tau), x[4] = -sqrt(3 - tau), with the golden section tau := (1 + sqrt(5))/2. They produce the discriminant(MP(1; 5, x)) = (Det(Vandermonde(4,[x[1],x[2],x[3],x[4]])))^2 = (20*sqrt(5))^2 = 2000. %Y A232627 Cf. A231188, A093819. %K A232627 nonn,easy %O A232627 1,3 %A A232627 _Wolfdieter Lang_, Dec 12 2013