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 | 0 |
| 1 | 1 |
| 2 | 6 |
| 3 | 21 |
| 4 | 58 |
| 5 | 141 |
| 6 | 318 |
| 7 | 685 |
| 8 | 1434 |
| 9 | 2949 |
| 10 | 5998 |
| 11 | 12117 |
| 12 | 24378 |
| 13 | 48925 |
| 14 | 98046 |
| 15 | 196317 |
| 16 | 392890 |
| 17 | 786069 |
| 18 | 1572462 |
| 19 | 3145285 |
| 20 | 6290970 |
| 21 | 12582381 |
| 22 | 25165246 |
| 23 | 50331021 |
| 24 | 100662618 |
| 25 | 201325861 |
| 26 | 402652398 |
| 27 | 805305525 |
| 28 | 1610611834 |
| 29 | 3221224509 |