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 | 0 |
| 1 | 1 |
| 2 | 2252 |
| 3 | 111753 |
| 4 | 1297504 |
| 5 | 7120505 |
| 6 | 25461756 |
| 7 | 70250257 |
| 8 | 163191008 |
| 9 | 335493009 |
| 10 | 629597260 |
| 11 | 1100904761 |
| 12 | 1819504512 |
| 13 | 2871901513 |
| 14 | 4362744764 |
| 15 | 6416555265 |
| 16 | 9179454016 |
| 17 | 12820890017 |
| 18 | 17535368268 |
| 19 | 23544177769 |
| 20 | 31097119520 |
| 21 | 40474234521 |
| 22 | 51987531772 |
| 23 | 65982716273 |
| 24 | 82840917024 |
| 25 | 102980415025 |
| 26 | 126858371276 |
| 27 | 154972554777 |