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 A089037 #13 Jul 09 2018 02:46:27
%S A089037 1,30,15500,453375000,95367431640625,1200572419921875000000,
%T A089037 216114100769531250000000000000,
%U A089037 2795257557110966548919677734375000000000,209657627533594448152542114257812500000000000000000,1062251098375118429310154377631647548696491867303848266601562500
%N A089037 Number of n X n matrices over GF(5) with characteristic polynomial x^n - 1.
%H A089037 I. Reiner, <a href="https://projecteuclid.org/euclid.ijm/1255629830">On the number of matrices with given characteristic polynomial</a>, Illinois J. Math. 5 1961 324-329.
%o A089037 (PARI) \\ see Reiner reference.
%o A089037 F(u,r)={prod(i=1, r, (1-u^(-i)))}
%o A089037 a(n, q=5)={my(D=ffgen(q)); my(f=factor(D^0*(x^n-1))); q^(n^2-n)*F(q,n)/prod(i=1, #f~, F(q^poldegree(f[i,1]), f[i,2]))} \\ _Andrew Howroyd_, Jul 08 2018
%Y A089037 Cf. A088654, A089035, A089036.
%K A089037 nonn
%O A089037 1,2
%A A089037 Yuval Dekel (dekelyuval(AT)hotmail.com) and _W. Edwin Clark_, Nov 29 2003
%E A089037 Offset corrected and a(8)-a(10) from _Andrew Howroyd_, Jul 08 2018