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 A099904 #3 Mar 31 2012 13:20:25
%S A099904 2,18,36,100,75,147,98,18,45,605,121,169,1183,7,1,289,289,361,361,1,
%T A099904 11,5819,529,1,13,13,1,841,841,961,961,1,17,17,1,1369,26011,19,1,1681,
%U A099904 1681,1849,1849,1,23,50807,2209,1,1,1,1,2809,2809,1,1,1,29,100949,3481,3721
%N A099904 Numerator of sum of all matrix elements of N X N matrix M(i,j) = i^3+j^3, (i,j = 1..n) divided by n!.
%C A099904 Sum M(i,j) (i,j = 1..n) is A099903(n). a(n) is an irregular sequence with highest champions belonging to Pentagonal pyramidal numbers n^2*(n+1)/2 (A002411) and n/2*(n+1)^2 (A006002).
%F A099904 a(n) = Numerator[1/n!*Sum[Sum[(i^3+j^3), {i, 1, n}], {j, 1, n}]] a(n) = Numerator[1/2 * (n^3)*(n+1)^2 /n! ].
%e A099904 A099903(n)/n! begins 2, 18, 36, 100/3, 75/4, 147/20, 98/45, 18/35, 45/448, ... So a(6) = 147.
%t A099904 Table[ Numerator[ Sum[(i^3 + j^3), {i, n}, {j, n}]/n! ], {n, 60}]
%Y A099904 Cf. A099903, A019584, A098077, A002411, A006002.
%K A099904 nonn
%O A099904 1,1
%A A099904 _Alexander Adamchuk_, Oct 29 2004