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 | 1 |
| 2 | 19 |
| 3 | 125 |
| 4 | 743 |
| 5 | 4345 |
| 6 | 25339 |
| 7 | 147701 |
| 8 | 860879 |
| 9 | 5017585 |
| 10 | 29244643 |
| 11 | 170450285 |
| 12 | 993457079 |
| 13 | 5790292201 |
| 14 | 33748296139 |
| 15 | 196699484645 |
| 16 | 1146448611743 |
| 17 | 6681992185825 |
| 18 | 38945504503219 |
| 19 | 226991034833501 |
| 20 | 1323000704497799 |
| 21 | 7711013192153305 |
| 22 | 44943078448422043 |