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 A268848 #15 Mar 02 2016 17:30:29
%S A268848 1,1,251,729811,10258694241,449363984934526,47342758641593552281,
%T A268848 10162884447920460534301136,3969183064899133655031651559801,
%U A268848 2599293828638212400913690945686101111,2683885055441747960475755652405552969614101
%N A268848 Number of sequences with 5 copies each of 1,2,...,n and longest increasing subsequence of length n.
%H A268848 Alois P. Heinz and Vaclav Kotesovec, <a href="/A268848/b268848.txt">Table of n, a(n) for n = 0..100</a> (terms 0..50 from Alois P. Heinz)
%H A268848 J. D. Horton and A. Kurn, Counting sequences with complete increasing subsequences, Congressus Numerantium, 33 (1981), 75-80. <a href="http://www.ams.org/mathscinet-getitem?mr=681905">MR 681905</a>
%F A268848 a(n) ~ sqrt(5) * (3125/24)^n * n^(4*n) / exp(4*n+4). - _Vaclav Kotesovec_, Feb 21 2016
%t A268848 Table[Sum[Sum[Sum[Sum[k!/(i1!*i2!*i3!*i4!*(k - i1 - i2 - i3 - i4)!)*(5*k)!/(i1 + 2*i2 + 3*i3 + 4*i4 + 5*(k - i1 - i2 - i3 - i4))!*(-1)^(i1 + 2*i2 + 3*i3 + 4*i4 + 5*(k - i1 - i2 - i3 - i4) - k)/(24^i1*6^i2*2^ i3), {i4, 0, k - i1 - i2 - i3}], {i3, 0, k - i1 - i2}], {i2, 0, k - i1}], {i1, 0, k}], {k, 0, 15}] (* _Vaclav Kotesovec_, Mar 02 2016, after Horton and Kurn *)
%Y A268848 Row n=5 of A047909.
%K A268848 nonn
%O A268848 0,3
%A A268848 _Alois P. Heinz_, Feb 14 2016