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 | 1 |
| 3 | 3 |
| 4 | 11 |
| 5 | 56 |
| 6 | 359 |
| 7 | 2597 |
| 8 | 20386 |
| 9 | 167819 |
| 10 | 1429815 |
| 11 | 12500748 |
| 12 | 111595289 |
| 13 | 1013544057 |
| 14 | 9340950309 |
| 15 | 87176935700 |
| 16 | 822559721606 |
| 17 | 7836316493485 |
| 18 | 75293711520236 |
| 19 | 728968295958626 |
| 20 | 7105984356424859 |
| 21 | 69697524828651997 |
| 22 | 687448151462822966 |
| 23 | 6815174949649428254 |