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 A192003 #15 Oct 02 2013 19:08:41 %S A192003 3,1,0,-1,-1,-2,-1,-1,-3,1,1,-2,1,1,-5,-1,-1,1,-1,1,7,1,1,-2,-1,1,-3, %T A192003 1,-1,1,-1,-1,-11,1,1,1,1,1,13,1,-1,1,-1,1,1,1,1,-2,-1,1,-17,1,-1,1,1, %U A192003 1,19,1,1,1,1,1,1,-1,1,1,-1,1,-23,1,1,1,1,1,-5,1,1,1,-1,1 %N A192003 Row sums of array A187360: minimal polynomials of 2*cos(Pi/n) evaluated for x=1. %F A192003 a(n) = sum(A187360(n,m),m=0..A055034(n)), n>=1. %F A192003 a(n) = C(n,x=1), with the minimal (monic and integer) polynomial C(n,x) of 2*cos(Pi/n). %Y A192003 Cf. A187360, A055034, A192004. %K A192003 sign,easy %O A192003 1,1 %A A192003 _Wolfdieter Lang_, Jul 14 2011