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 | 0 |
| 2 | 3 |
| 3 | 2 |
| 4 | 19 |
| 5 | 30 |
| 6 | 143 |
| 7 | 322 |
| 8 | 1179 |
| 9 | 3110 |
| 10 | 10183 |
| 11 | 28842 |
| 12 | 89939 |
| 13 | 262990 |
| 14 | 802623 |
| 15 | 2380562 |
| 16 | 7196299 |
| 17 | 21479670 |
| 18 | 64657463 |
| 19 | 193535482 |
| 20 | 581480259 |
| 21 | 1742693150 |
| 22 | 5231574703 |
| 23 | 15687733602 |
| 24 | 47077181819 |
| 25 | 141203583430 |
| 26 | 423666674343 |