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 | 3 |
| 2 | 23 |
| 3 | 165 |
| 4 | 3802 |
| 5 | 21385 |
| 6 | 993605 |
| 7 | 15198435 |
| 8 | 394722916 |
| 9 | 3814933122 |
| 10 | 447827009070 |
| 11 | 5229570190845 |
| 12 | 862250830559382 |
| 13 | 11802457085079375 |
| 14 | 173406732097447849 |
| 15 | 5443765223302501095 |
| 16 | 1545512798280174555832 |
| 17 | 27361456077246355572508 |
| 18 | 9725198808628092900136884 |
| 19 | 191684785790597591594500398 |