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) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 5 |
| 5 | 10 |
| 6 | 35 |
| 7 | 102 |
| 8 | 360 |
| 9 | 1232 |
| 10 | 4427 |
| 11 | 15934 |
| 12 | 58465 |
| 13 | 215250 |
| 14 | 799593 |
| 15 | 2983204 |
| 16 | 11187200 |
| 17 | 42109450 |
| 18 | 159081482 |
| 19 | 602809326 |
| 20 | 2290679807 |
| 21 | 8726308212 |
| 22 | 33318645341 |
| 23 | 127479700198 |
| 24 | 488672244040 |
| 25 | 1876500180280 |