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 | 5 |
| 2 | 45 |
| 3 | 525 |
| 4 | 7065 |
| 5 | 104097 |
| 6 | 1632915 |
| 7 | 26817465 |
| 8 | 456137580 |
| 9 | 7975932715 |
| 10 | 142619162000 |
| 11 | 2597695379665 |
| 12 | 48053332283700 |
| 13 | 900703198101845 |