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) |
|---|---|
| 1 | 1 |
| 2 | 4 |
| 3 | 12 |
| 4 | 36 |
| 5 | 111 |
| 6 | 353 |
| 7 | 1154 |
| 8 | 3860 |
| 9 | 13155 |
| 10 | 45525 |
| 11 | 159561 |
| 12 | 565249 |
| 13 | 2020687 |
| 14 | 7280419 |
| 15 | 26410094 |
| 16 | 96378164 |
| 17 | 353576699 |
| 18 | 1303271309 |
| 19 | 4824150869 |
| 20 | 17925098069 |
| 21 | 66834680639 |
| 22 | 249981423899 |
| 23 | 937696277309 |
| 24 | 3526652828321 |
| 25 | 13295935057031 |
| 26 | 50240112815003 |