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 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 5 |
| 5 | 10 |
| 6 | 21 |
| 7 | 53 |
| 8 | 133 |
| 9 | 327 |
| 10 | 861 |
| 11 | 2361 |
| 12 | 6469 |
| 13 | 18168 |
| 14 | 52757 |
| 15 | 155221 |
| 16 | 463077 |
| 17 | 1412656 |
| 18 | 4379917 |
| 19 | 13747504 |
| 20 | 43834213 |
| 21 | 141866555 |
| 22 | 464650309 |
| 23 | 1541008295 |
| 24 | 5176660997 |
| 25 | 17586913779 |
| 26 | 60400627453 |
| 27 | 209746820056 |
| 28 | 735953607173 |
| 29 | 2607716976945 |
| 30 | 9330605338485 |