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) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 6 |
| 4 | 17 |
| 5 | 80 |
| 6 | 337 |
| 7 | 2240 |
| 8 | 14681 |
| 9 | 117010 |
| 10 | 1023941 |
| 11 | 10900472 |
| 12 | 108881665 |
| 13 | 1375544846 |
| 14 | 17732140805 |
| 15 | 247041590476 |
| 16 | 3605768497217 |
| 17 | 59990390084690 |
| 18 | 977383707751621 |
| 19 | 18214603019184800 |
| 20 | 337615168055209601 |
| 21 | 6763842079452393622 |
| 22 | 141262515443311046885 |