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 | 22 |
| 4 | 79 |
| 5 | 278 |
| 6 | 1021 |
| 7 | 3752 |
| 8 | 14023 |
| 9 | 52640 |
| 10 | 199248 |
| 11 | 757360 |
| 12 | 2892977 |
| 13 | 11088266 |
| 14 | 42640759 |
| 15 | 164413606 |
| 16 | 635490703 |
| 17 | 2461411460 |
| 18 | 9551605730 |
| 19 | 37126976390 |
| 20 | 144528973888 |
| 21 | 563386487780 |
| 22 | 2198826762318 |
| 23 | 8591331622208 |