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 | 6 |
| 3 | 24 |
| 4 | 105 |
| 5 | 385 |
| 6 | 1554 |
| 7 | 6063 |
| 8 | 23688 |
| 9 | 92610 |
| 10 | 362112 |
| 11 | 1416360 |
| 12 | 5539296 |
| 13 | 21663378 |
| 14 | 84725487 |
| 15 | 331362185 |
| 16 | 1295952084 |
| 17 | 5068450464 |
| 18 | 19822658688 |