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 | 21 |
| 2 | 231 |
| 3 | 1771 |
| 4 | 10626 |
| 5 | 53130 |
| 6 | 230230 |
| 7 | 888030 |
| 8 | 3108105 |
| 9 | 10015005 |
| 10 | 30045015 |
| 11 | 84504355 |
| 12 | 223651350 |
| 13 | 558350430 |
| 14 | 1318250890 |
| 15 | 2952624906 |
| 16 | 6296642121 |
| 17 | 12834146941 |
| 18 | 25098124271 |
| 19 | 47262174531 |
| 20 | 85990654178 |
| 21 | 151631858378 |
| 22 | 259857912678 |
| 23 | 433877085278 |
| 24 | 707369215553 |