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) |
|---|---|
| 5 | 462 |
| 6 | 6468 |
| 7 | 48048 |
| 8 | 252252 |
| 9 | 1051050 |
| 10 | 3699696 |
| 11 | 11435424 |
| 12 | 31855824 |
| 13 | 81477396 |
| 14 | 193993800 |
| 15 | 434546112 |
| 16 | 923410488 |
| 17 | 1873980108 |
| 18 | 3651858672 |
| 19 | 6864396000 |
| 20 | 12493200720 |
| 21 | 22086194130 |
| 22 | 38030772780 |
| 23 | 63935791920 |
| 24 | 105157552500 |
| 25 | 169513974630 |
| 26 | 268241893920 |
| 27 | 417265168320 |