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 | 0 |
| 1 | 5 |
| 2 | 54 |
| 3 | 539 |
| 4 | 5340 |
| 5 | 52865 |
| 6 | 523314 |
| 7 | 5180279 |
| 8 | 51279480 |
| 9 | 507614525 |
| 10 | 5024865774 |
| 11 | 49741043219 |
| 12 | 492385566420 |
| 13 | 4874114620985 |
| 14 | 48248760643434 |
| 15 | 477613491813359 |
| 16 | 4727886157490160 |
| 17 | 46801248083088245 |
| 18 | 463284594673392294 |
| 19 | 4586044698650834699 |
| 20 | 45397162391834954700 |