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 | 2 |
| 3 | 6 |
| 4 | 18 |
| 5 | 46 |
| 6 | 115 |
| 7 | 301 |
| 8 | 792 |
| 9 | 2068 |
| 10 | 5380 |
| 11 | 14020 |
| 12 | 36581 |
| 13 | 95413 |
| 14 | 248786 |
| 15 | 648714 |
| 16 | 1691686 |
| 17 | 4411530 |
| 18 | 11503991 |
| 19 | 29998953 |
| 20 | 78228640 |
| 21 | 203998184 |
| 22 | 531969064 |
| 23 | 1387222648 |
| 24 | 3617479225 |
| 25 | 9433351129 |
| 26 | 24599481138 |
| 27 | 64148406350 |
| 28 | 167280683834 |