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 | 1 |
| 3 | 2 |
| 4 | 7 |
| 5 | 23 |
| 6 | 112 |
| 7 | 607 |
| 8 | 3811 |
| 9 | 25413 |
| 10 | 178083 |
| 11 | 1279537 |
| 12 | 9371094 |
| 13 | 69513546 |
| 14 | 520878101 |
| 15 | 3934285874 |
| 16 | 29915913663 |
| 17 | 228779330204 |
| 18 | 1758309223457 |
| 19 | 13573319825615 |
| 20 | 105192814197984 |
| 21 | 818136047201932 |
| 22 | 6383528588447574 |