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 | 2 |
| 1 | 9 |
| 2 | 36 |
| 3 | 153 |
| 4 | 624 |
| 5 | 2584 |
| 6 | 10632 |
| 7 | 43865 |
| 8 | 180774 |
| 9 | 745347 |
| 10 | 3072528 |
| 11 | 12666854 |
| 12 | 52218790 |
| 13 | 215273737 |
| 14 | 887468000 |
| 15 | 3658604277 |
| 16 | 15082652352 |
| 17 | 62178493132 |
| 18 | 256331858332 |
| 19 | 1056732372729 |
| 20 | 4356396740786 |
| 21 | 17959318086575 |
| 22 | 74037587378784 |
| 23 | 305221185520298 |
| 24 | 1258279413185322 |