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 | 6 |
| 4 | 240 |
| 5 | 1010 |
| 6 | 4056 |
| 7 | 12068 |
| 8 | 30000 |
| 9 | 65628 |
| 10 | 130480 |
| 11 | 240856 |
| 12 | 418968 |
| 13 | 694200 |
| 14 | 1104488 |
| 15 | 1697820 |
| 16 | 2533856 |
| 17 | 3685668 |
| 18 | 5241600 |
| 19 | 7307248 |
| 20 | 10007560 |
| 21 | 13489056 |
| 22 | 17922168 |
| 23 | 23503700 |
| 24 | 30459408 |
| 25 | 39046700 |
| 26 | 49557456 |
| 27 | 62320968 |
| 28 | 77707000 |
| 29 | 96128968 |
| 30 | 118047240 |
| 31 | 143972556 |