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 | 7 |
| 3 | 24 |
| 4 | 81 |
| 5 | 270 |
| 6 | 891 |
| 7 | 2916 |
| 8 | 9477 |
| 9 | 30618 |
| 10 | 98415 |
| 11 | 314928 |
| 12 | 1003833 |
| 13 | 3188646 |
| 14 | 10097379 |
| 15 | 31886460 |
| 16 | 100442349 |
| 17 | 315675954 |
| 18 | 990074583 |
| 19 | 3099363912 |
| 20 | 9685512225 |
| 21 | 30218798142 |
| 22 | 94143178827 |
| 23 | 292889889684 |
| 24 | 910050728661 |
| 25 | 2824295364810 |