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 | 1 |
| 8 | 7 |
| 9 | 35 |
| 10 | 170 |
| 11 | 847 |
| 12 | 4408 |
| 13 | 24297 |
| 14 | 143270 |
| 15 | 901491 |
| 16 | 5985278 |
| 17 | 41175203 |
| 18 | 287813284 |
| 19 | 2009864185 |
| 20 | 13848061942 |
| 21 | 93369988436 |
| 22 | 613030637339 |
| 23 | 3908996099141 |
| 24 | 24179747870890 |
| 25 | 145056691643428 |
| 26 | 844229016035010 |
| 27 | 4769751989333029 |
| 28 | 26181645303024760 |
| 29 | 139750488576152520 |