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) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 7 |
| 3 | 21 |
| 4 | 78 |
| 5 | 260 |
| 6 | 988 |
| 7 | 3458 |
| 8 | 13300 |
| 9 | 47880 |
| 10 | 185535 |
| 11 | 680295 |
| 12 | 2649570 |
| 13 | 9841260 |
| 14 | 38470380 |
| 15 | 144263925 |
| 16 | 565514586 |
| 17 | 2136388436 |
| 18 | 8392954570 |
| 19 | 31893227366 |
| 20 | 125515281892 |
| 21 | 479240167224 |
| 22 | 1888770070824 |
| 23 | 7240285271492 |
| 24 | 28569774314536 |
| 25 | 109883747363600 |
| 26 | 434040802086220 |