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 | 5 |
| 4 | 14 |
| 5 | 42 |
| 6 | 132 |
| 7 | 428 |
| 8 | 1415 |
| 9 | 4730 |
| 10 | 15901 |
| 11 | 53593 |
| 12 | 180809 |
| 13 | 610157 |
| 14 | 2058962 |
| 15 | 6947145 |
| 16 | 23437854 |
| 17 | 79067006 |
| 18 | 266717300 |
| 19 | 899693960 |
| 20 | 3034814143 |
| 21 | 10236853534 |
| 22 | 34530252629 |
| 23 | 116475001757 |
| 24 | 392885252033 |