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 A019580 #6 Mar 28 2019 11:24:45 %S A019580 1,20,375,7560,167825,4110120,110602800,3252075750,103881924300, %T A019580 3585467886000,133052005386300,5284678706307000,223761183682286250, %U A019580 10063370411081988000,479152851159102120000,24082014064135799772000 %N A019580 Place n distinguishable balls in n boxes (in n^n ways); let f(n,k) = number of ways that max in any box is k, for 1<=k<=n; sequence gives f(n,4)/n. %Y A019580 Cf. A019576. %K A019580 nonn %O A019580 4,2 %A A019580 Lee Corbin (lcorbin(AT)tsoft.com) %E A019580 More terms from _Sean A. Irvine_, Mar 27 2019