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 | 7 |
| 1 | 7 |
| 2 | 13 |
| 3 | 37 |
| 4 | 145 |
| 5 | 721 |
| 6 | 4321 |
| 7 | 30241 |
| 8 | 241921 |
| 9 | 2177281 |
| 10 | 21772801 |
| 11 | 239500801 |
| 12 | 2874009601 |
| 13 | 37362124801 |
| 14 | 523069747201 |
| 15 | 7846046208001 |
| 16 | 125536739328001 |
| 17 | 2134124568576001 |
| 18 | 38414242234368001 |
| 19 | 729870602452992001 |