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 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 0 |
| 6 | 0 |
| 7 | 0 |
| 8 | 6 |
| 9 | 13 |
| 10 | 57 |
| 11 | 141 |
| 12 | 465 |
| 13 | 1224 |
| 14 | 3956 |
| 15 | 11599 |
| 16 | 36538 |
| 17 | 107415 |
| 18 | 327250 |
| 19 | 972040 |
| 20 | 2957488 |
| 21 | 8879327 |
| 22 | 26943317 |