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 | 1 |
| 3 | 2 |
| 4 | 5 |
| 5 | 12 |
| 6 | 31 |
| 7 | 80 |
| 8 | 214 |
| 9 | 576 |
| 10 | 1595 |
| 11 | 4448 |
| 12 | 12625 |
| 13 | 36146 |
| 14 | 104662 |
| 15 | 305251 |
| 16 | 897417 |
| 17 | 2654072 |
| 18 | 7895394 |
| 19 | 23601441 |
| 20 | 70871693 |
| 21 | 213660535 |
| 22 | 646484951 |
| 23 | 1962507610 |
| 24 | 5975425743 |
| 25 | 18243789556 |
| 26 | 55841543003 |
| 27 | 171320324878 |
| 28 | 526738779846 |
| 29 | 1622739134873 |
| 30 | 5008518981670 |