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 | 9 |
| 2 | 405 |
| 3 | 23085 |
| 4 | 1454355 |
| 5 | 96860043 |
| 6 | 6683342967 |
| 7 | 472607824095 |
| 8 | 34027763334840 |
| 9 | 2484026723443320 |
| 10 | 183321172190117016 |
| 11 | 13649094547609621464 |
| 12 | 1023682091070721609800 |
| 13 | 77248625487721376862600 |
| 14 | 5859860019140007302005800 |
| 15 | 446521333458468556412841960 |
| 16 | 34158882009572844565582409940 |