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 | 13 |
| 3 | 42 |
| 4 | 117 |
| 5 | 310 |
| 6 | 785 |
| 7 | 1896 |
| 8 | 4433 |
| 9 | 10062 |
| 10 | 22248 |
| 11 | 48080 |
| 12 | 101821 |
| 13 | 211682 |
| 14 | 432795 |
| 15 | 871520 |
| 16 | 1730491 |
| 17 | 3391894 |
| 18 | 6568996 |
| 19 | 12580316 |
| 20 | 23841774 |
| 21 | 44742634 |
| 22 | 83193865 |
| 23 | 153347110 |
| 24 | 280336704 |
| 25 | 508499474 |
| 26 | 915540681 |
| 27 | 1636805438 |
| 28 | 2906642396 |
| 29 | 5128530946 |
| 30 | 8993376689 |