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) |
|---|---|
| 2 | 1 |
| 3 | 7 |
| 4 | 39 |
| 5 | 201 |
| 6 | 1000 |
| 7 | 4885 |
| 8 | 23621 |
| 9 | 113543 |
| 10 | 543895 |
| 11 | 2600204 |
| 12 | 12417829 |
| 13 | 59278440 |
| 14 | 282969385 |
| 15 | 1351124510 |
| 16 | 6454283276 |
| 17 | 30849969965 |
| 18 | 147555219782 |
| 19 | 706274470775 |
| 20 | 3383203356648 |
| 21 | 16219148141581 |
| 22 | 77817618006364 |
| 23 | 373661751926702 |