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 | 2 |
| 2 | 5 |
| 3 | 32 |
| 4 | 286 |
| 5 | 3038 |
| 6 | 35870 |
| 7 | 454880 |
| 8 | 6073311 |
| 9 | 84302270 |
| 10 | 1206291308 |
| 11 | 17687468032 |
| 12 | 264593385735 |
| 13 | 4024945917314 |
| 14 | 62101640836955 |
| 15 | 969921269646560 |
| 16 | 15309505269479942 |
| 17 | 243897741785306000 |
| 18 | 3917478255634975373 |
| 19 | 63381933612745811168 |
| 20 | 1032176017566352265886 |
| 21 | 16907912684907490828614 |