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 | 2 |
| 2 | 7 |
| 3 | 44 |
| 4 | 401 |
| 5 | 4682 |
| 6 | 66431 |
| 7 | 1111112 |
| 8 | 21435889 |
| 9 | 469070942 |
| 10 | 11488207655 |
| 11 | 311505013052 |
| 12 | 9267595563617 |
| 13 | 300239975158034 |
| 14 | 10523614159962559 |
| 15 | 396861212733968144 |
| 16 | 16024522975978953761 |
| 17 | 689852631578947368422 |
| 18 | 31544039619835776489479 |