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 | 2 |
| 3 | 8 |
| 4 | 48 |
| 5 | 256 |
| 6 | 1280 |
| 7 | 6912 |
| 8 | 39424 |
| 9 | 212992 |
| 10 | 1118208 |
| 11 | 6553600 |
| 12 | 36765696 |
| 13 | 199229440 |
| 14 | 1133117440 |
| 15 | 6499598336 |
| 16 | 36175872000 |
| 17 | 200655503360 |
| 18 | 1167945891840 |
| 19 | 6620826304512 |
| 20 | 36681168191488 |
| 21 | 212364657950720 |
| 22 | 1219998345330688 |
| 23 | 6864598984556544 |
| 24 | 38958828003262464 |
| 25 | 226089827240509440 |
| 26 | 1287455960675123200 |