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 A118987 #17 Jun 22 2024 03:39:51 %S A118987 1,2,2,3,5,7,11,19,40,91,214 %N A118987 Number of different values taken by the determinant of a symmetric real (+1,-1)-matrix of order n. %H A118987 Minfeng Wang, <a href="/A118987/a118987.cpp.txt">C++ program to calculate A118987</a> %Y A118987 Cf. A089472, A118988, A118985. %Y A118987 Cf. A006125 (number of symmetric real (+1,-1)-matrices of order (n-1)). %K A118987 nonn,more %O A118987 0,2 %A A118987 _Giovanni Resta_, May 08 2006 %E A118987 a(0)=1 prepended by _Alois P. Heinz_, Mar 16 2019 %E A118987 a(8) from _Minfeng Wang_, Jun 10 2024 %E A118987 a(9)-a(10) from _Minfeng Wang_, Jun 12 2024