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 A306002 #10 Jun 18 2018 03:12:40
%S A306002 3,11,157,8825,2681903
%N A306002 Number of distinct real eigenvalues of n X n matrices with elements {-1, 0, +1}.
%D A306002 Steven E. Thornton & Robert M. Corless, The Bohemian Eigenvalue Project, Poster Presented at The International Symposium on Symbolic and Algebraic Computation (ISSAC 2016). Wilfrid Laurier University, July 19-22, 2016.
%H A306002 Steven E. Thornton & Robert M. Corless, <a href="http://www.bohemianeigenvalues.com/">The Bohemian Eigenvalue Project</a>.
%Y A306002 Number of distinct eigenvalues: A271570.
%Y A306002 Number of characteristic polynomials: A272658.
%K A306002 nonn,hard,more
%O A306002 1,1
%A A306002 _Steven E. Thornton_, Jun 16 2018