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 | 120 |
| 2 | 1440 |
| 3 | 6720 |
| 4 | 21504 |
| 5 | 55296 |
| 6 | 122880 |
| 7 | 245640 |
| 8 | 452880 |
| 9 | 783144 |
| 10 | 1285536 |
| 11 | 2021040 |
| 12 | 3063840 |
| 13 | 4502640 |
| 14 | 6441984 |
| 15 | 9003576 |
| 16 | 12327600 |
| 17 | 16574040 |
| 18 | 21924000 |
| 19 | 28581024 |
| 20 | 36772416 |
| 21 | 46750560 |
| 22 | 58794240 |
| 23 | 73209960 |
| 24 | 90333264 |
| 25 | 110530056 |