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 | 5 |
| 3 | 11 |
| 4 | 25 |
| 5 | 57 |
| 6 | 129 |
| 7 | 291 |
| 8 | 656 |
| 9 | 1477 |
| 10 | 3325 |
| 11 | 7481 |
| 12 | 16834 |
| 13 | 37876 |
| 14 | 85222 |
| 15 | 191751 |
| 16 | 431439 |
| 17 | 970739 |
| 18 | 2184164 |
| 19 | 4914369 |
| 20 | 11057332 |
| 21 | 24878997 |
| 22 | 55977744 |
| 23 | 125949925 |
| 24 | 283387333 |
| 25 | 637621500 |
| 26 | 1434648375 |
| 27 | 3227958844 |
| 28 | 7262907400 |
| 29 | 16341541651 |