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 | 3 |
| 2 | 18 |
| 3 | 160 |
| 4 | 1752 |
| 5 | 21504 |
| 6 | 282304 |
| 7 | 3867840 |
| 8 | 54547200 |
| 9 | 785255680 |
| 10 | 11478167040 |
| 11 | 169748686848 |
| 12 | 2533556365312 |
| 13 | 38094656593920 |
| 14 | 576271774875648 |
| 15 | 8761529890717696 |
| 16 | 133776598692003840 |
| 17 | 2050020136793604096 |