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 | 11 |
| 1 | 1 |
| 2 | 81 |
| 3 | 391 |
| 4 | 3561 |
| 5 | 25531 |
| 6 | 199821 |
| 7 | 1511931 |
| 8 | 11589281 |
| 9 | 88389661 |
| 10 | 675443291 |
| 11 | 5157630831 |
| 12 | 39394699881 |
| 13 | 300868345701 |
| 14 | 2297915763861 |
| 15 | 17550293888221 |
| 16 | 134040955378561 |
| 17 | 1023739686467981 |
| 18 | 7818833928607761 |
| 19 | 59716490127924211 |
| 20 | 456085875187977011 |
| 21 | 3483364700645591901 |