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 | 25 |
| 2 | 350 |
| 3 | 3625 |
| 4 | 30825 |
| 5 | 227005 |
| 6 | 1495225 |
| 7 | 8998625 |
| 8 | 50231225 |
| 9 | 262982425 |
| 10 | 1302361670 |
| 11 | 6141852925 |
| 12 | 27731605150 |
| 13 | 120415590250 |
| 14 | 504692324800 |
| 15 | 2048151994275 |
| 16 | 8069513499800 |
| 17 | 30937269482500 |
| 18 | 115647629802975 |