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 | 13 |
| 2 | 185 |
| 3 | 3013 |
| 4 | 51009 |
| 5 | 864453 |
| 6 | 14514449 |
| 7 | 241137749 |
| 8 | 3969473217 |
| 9 | 64867543333 |
| 10 | 1054153461745 |
| 11 | 17059836799733 |
| 12 | 275240835803937 |
| 13 | 4430702562116805 |
| 14 | 71206049773837905 |
| 15 | 1142980976834497173 |
| 16 | 18330756374528899457 |
| 17 | 293794963549100393573 |
| 18 | 4706588394482611291313 |
| 19 | 75373885078381735479861 |