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 | 3 |
| 3 | 13 |
| 4 | 85 |
| 5 | 806 |
| 6 | 9583 |
| 7 | 140050 |
| 8 | 2434185 |
| 9 | 49031983 |
| 10 | 1122332211 |
| 11 | 28768909071 |
| 12 | 816222524845 |
| 13 | 25389827448220 |
| 14 | 859153189293015 |
| 15 | 31417769545499716 |
| 16 | 1234605616147931665 |
| 17 | 51882038993710230701 |
| 18 | 2321660210597147557819 |