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 | 3 |
| 4 | 10 |
| 5 | 41 |
| 6 | 186 |
| 7 | 922 |
| 8 | 4911 |
| 9 | 27830 |
| 10 | 166656 |
| 11 | 1049410 |
| 12 | 6922476 |
| 13 | 47698148 |
| 14 | 342483885 |
| 15 | 2557538781 |
| 16 | 19829608532 |
| 17 | 159393394129 |
| 18 | 1326509171669 |
| 19 | 11415703608635 |
| 20 | 101473987987073 |
| 21 | 930688926616454 |
| 22 | 8798656042121634 |