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 | 4 |
| 2 | 6 |
| 3 | 18 |
| 4 | 42 |
| 5 | 108 |
| 6 | 268 |
| 7 | 676 |
| 8 | 1694 |
| 9 | 4258 |
| 10 | 10690 |
| 11 | 26852 |
| 12 | 67436 |
| 13 | 169372 |
| 14 | 425382 |
| 15 | 1068370 |
| 16 | 2683258 |
| 17 | 6739132 |
| 18 | 16925644 |
| 19 | 42509556 |
| 20 | 106764750 |
| 21 | 268144706 |
| 22 | 673458066 |
| 23 | 1691421684 |
| 24 | 4248085292 |
| 25 | 10669266476 |
| 26 | 26796365718 |
| 27 | 67300335730 |
| 28 | 169027965834 |