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 | 4 |
| 2 | 14 |
| 3 | 47 |
| 4 | 156 |
| 5 | 517 |
| 6 | 1714 |
| 7 | 5684 |
| 8 | 18851 |
| 9 | 62520 |
| 10 | 207349 |
| 11 | 687676 |
| 12 | 2280686 |
| 13 | 7563923 |
| 14 | 25085844 |
| 15 | 83197513 |
| 16 | 275925586 |
| 17 | 915110636 |
| 18 | 3034975799 |
| 19 | 10065534960 |
| 20 | 33382471801 |
| 21 | 110713382644 |
| 22 | 367182309614 |
| 23 | 1217764693607 |
| 24 | 4038731742156 |
| 25 | 13394504020957 |
| 26 | 44423039068114 |