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 | 0 |
| 2 | 2 |
| 3 | 5 |
| 4 | 44 |
| 5 | 199 |
| 6 | 1182 |
| 7 | 6102 |
| 8 | 33710 |
| 9 | 180382 |
| 10 | 980490 |
| 11 | 5289023 |
| 12 | 28634131 |
| 13 | 154747076 |
| 14 | 837016897 |
| 15 | 4525504274 |
| 16 | 24472972752 |
| 17 | 132331839901 |
| 18 | 715586695597 |
| 19 | 3869459738102 |
| 20 | 20923925463760 |
| 21 | 113144565987295 |
| 22 | 611822365490334 |