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) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 9 |
| 3 | 24 |
| 4 | 170 |
| 5 | 240 |
| 6 | 2415 |
| 7 | 7000 |
| 8 | 30744 |
| 9 | 45360 |
| 10 | 741510 |
| 11 | 1108800 |
| 12 | 21673080 |
| 13 | 32744712 |
| 14 | 49684635 |
| 15 | 151351200 |
| 16 | 3932288360 |
| 17 | 6028102080 |
| 18 | 176061013128 |
| 19 | 271314186000 |
| 20 | 419047770960 |
| 21 | 648560072160 |
| 22 | 23130491854470 |
| 23 | 35929017476352 |