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 | 1 |
| 2 | 18 |
| 3 | 1701 |
| 4 | 278478 |
| 5 | 56542698 |
| 6 | 12838905972 |
| 7 | 3121895416077 |
| 8 | 795077021525526 |
| 9 | 209364566760439038 |
| 10 | 56540432581528153788 |
| 11 | 15573764062988183490786 |
| 12 | 4358381303784085630372620 |
| 13 | 1235729432868053981694246324 |