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 | 2 |
| 3 | 5 |
| 4 | 22 |
| 5 | 181 |
| 6 | 203 |
| 7 | 790 |
| 8 | 993 |
| 9 | 30580 |
| 10 | 31573 |
| 11 | 125299 |
| 12 | 156872 |
| 13 | 1380275 |
| 14 | 5677972 |
| 15 | 12736219 |
| 16 | 18414191 |
| 17 | 31150410 |
| 18 | 1949739611 |
| 19 | 1980890021 |
| 20 | 3930629632 |
| 21 | 9842149285 |
| 22 | 43299226772 |
| 23 | 356235963461 |
| 24 | 399535190233 |
| 25 | 1554841534160 |
| 26 | 1954376724393 |
| 27 | 60186143265950 |
| 28 | 62140519990343 |