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 | 2 |
| 3 | 6 |
| 4 | 23 |
| 5 | 107 |
| 6 | 582 |
| 7 | 3622 |
| 8 | 25369 |
| 9 | 197523 |
| 10 | 1692535 |
| 11 | 15829557 |
| 12 | 160463512 |
| 13 | 1752529064 |
| 14 | 20516018396 |
| 15 | 256273980368 |
| 16 | 3402364791737 |
| 17 | 47841014687039 |
| 18 | 710242228143271 |
| 19 | 11101522062378069 |
| 20 | 182234745428876525 |
| 21 | 3134424458578405569 |
| 22 | 56371116965252450338 |