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 A225931 #7 May 22 2013 20:32:14 %S A225931 95,273,539,1156,3566,5603,8751,18346,34364,75443,95656,146882,308254, %T A225931 426656,576345,762412,990326,1120595,1985636,2976016,3591434,5103526, %U A225931 6017672,8208724,12553402,14326796,17326739,20785106,26163886,29214704,39981062,44156775 %N A225931 Number of conjugacy classes in Chevalley group F_4(q) as q runs through the prime powers. %H A225931 Eric M. Schmidt, <a href="/A225931/b225931.txt">Table of n, a(n) for n = 1..1000</a> %H A225931 Frank Luebeck, <a href="http://www.math.rwth-aachen.de/~Frank.Luebeck/chev/nrclasses/nrclasses.html">Numbers of Conjugacy Classes in Finite Groups of Lie Type</a>. %F A225931 Let q be the n-th prime power. %F A225931 a(n) = q^4 + 2q^3 + 6q^2 + 10q + 19 if q == 0 mod 2. %F A225931 a(n) = q^4 + 2q^3 + 7q^2 + 15q + 30 if q == 0 mod 3. %F A225931 a(n) = q^4 + 2q^3 + 7q^2 + 15q + 31 otherwise. %o A225931 (Sage) def A225931(q) : return q^4 + 2*q^3 + (6*q^2 + 10*q + 19 if q%2==0 else 7*q^2 + 15*q + 30 if q%3==0 else 7*q^2 + 15*q + 31) %Y A225931 Cf. A188161, A224790, A225928 - A225938. %K A225931 nonn %O A225931 1,1 %A A225931 _Eric M. Schmidt_, May 21 2013