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 | 15 |
| 3 | 192 |
| 4 | 2415 |
| 5 | 30305 |
| 6 | 380160 |
| 7 | 4768673 |
| 8 | 59817135 |
| 9 | 750331584 |
| 10 | 9411975375 |
| 11 | 118061508289 |
| 12 | 1480934568960 |
| 13 | 18576479568193 |
| 14 | 233018797965135 |
| 15 | 2922930580320960 |
| 16 | 36664523428884015 |
| 17 | 459910778352898337 |
| 18 | 5769007865476035840 |
| 19 | 72365017995700730081 |
| 20 | 907729015392142395375 |