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 | 9 |
| 3 | 171 |
| 4 | 2439 |
| 5 | 30951 |
| 6 | 368559 |
| 7 | 4217031 |
| 8 | 46953279 |
| 9 | 512579511 |
| 10 | 5513215599 |
| 11 | 58618940391 |
| 12 | 617570463519 |
| 13 | 6458134171671 |
| 14 | 67123207545039 |
| 15 | 694108867905351 |
| 16 | 7146979811148159 |
| 17 | 73322818300333431 |
| 18 | 749905364703000879 |
| 19 | 7649148282327007911 |
| 20 | 77842334540943071199 |