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 | 1 |
| 2 | 3 |
| 3 | 33 |
| 4 | 855 |
| 5 | 40475 |
| 6 | 3039204 |
| 7 | 331630320 |
| 8 | 49563943161 |
| 9 | 9722245517970 |
| 10 | 2423526680920125 |
| 11 | 748560249534719259 |
| 12 | 280702726068079355157 |
| 13 | 125661789748507921799800 |
| 14 | 66215986172320048509110050 |