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 | 1 |
| 2 | 5 |
| 3 | 16 |
| 4 | 53 |
| 5 | 228 |
| 6 | 281 |
| 7 | 8658 |
| 8 | 8939 |
| 9 | 44414 |
| 10 | 142181 |
| 11 | 470957 |
| 12 | 2026009 |
| 13 | 2496966 |
| 14 | 76934989 |
| 15 | 79431955 |
| 16 | 394662809 |
| 17 | 1263420382 |
| 18 | 4184923955 |
| 19 | 18003116202 |
| 20 | 22188040157 |
| 21 | 683644320912 |
| 22 | 705832361069 |
| 23 | 3506973765188 |
| 24 | 11226753656633 |
| 25 | 37187234735087 |
| 26 | 159975692596981 |