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 | 10 |
| 3 | 84 |
| 4 | 1092 |
| 5 | 15630 |
| 6 | 284700 |
| 7 | 5764808 |
| 8 | 134744072 |
| 9 | 3486961557 |
| 10 | 100097666500 |
| 11 | 3138428376732 |
| 12 | 107019534520152 |
| 13 | 3937376385699302 |
| 14 | 155577590681061500 |
| 15 | 6568408813691796120 |
| 16 | 295152408847700721680 |
| 17 | 14063084452067724991026 |
| 18 | 708238048886859220660710 |