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 | 1 |
| 4 | 4 |
| 5 | 5 |
| 6 | 15 |
| 7 | 21 |
| 8 | 56 |
| 9 | 246 |
| 10 | 525 |
| 11 | 1573 |
| 12 | 5764 |
| 13 | 14092 |
| 14 | 41405 |
| 15 | 136995 |
| 16 | 772552 |
| 17 | 2148290 |
| 18 | 8806629 |
| 19 | 31679365 |
| 20 | 155743665 |
| 21 | 495240074 |
| 22 | 2049655762 |
| 23 | 7403470138 |
| 24 | 32627363920 |
| 25 | 207316068370 |
| 26 | 784695179515 |
| 27 | 3721285661481 |
| 28 | 16967347935561 |
| 29 | 82192321793926 |
| 30 | 455572563875425 |