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) |
|---|---|
| 4 | 1 |
| 5 | 61 |
| 6 | 5551 |
| 7 | 433771 |
| 8 | 35569222 |
| 9 | 2869444942 |
| 10 | 232740363922 |
| 11 | 18843459775162 |
| 12 | 1526550040078063 |
| 13 | 123644349019377043 |
| 14 | 10015359787639069513 |
| 15 | 811239619864365082573 |
| 16 | 65710531328480659504924 |