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.
| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 25 |
| 2 | 350 |
| 3 | 3575 |
| 4 | 29575 |
| 5 | 209381 |
| 6 | 1312075 |
| 7 | 7443825 |
| 8 | 38854075 |
| 9 | 188836375 |
| 10 | 862496902 |
| 11 | 3729343275 |
| 12 | 15356254650 |
| 13 | 60511763600 |
| 14 | 229125615600 |
| 15 | 836555203223 |
| 16 | 2953900713000 |
| 17 | 10113407774450 |
| 18 | 33649438734125 |
| 19 | 109017926343725 |
| 20 | 344525085375315 |
| 21 | 1063718962906450 |