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 | 1 |
| 2 | 2 |
| 3 | 5 |
| 4 | 14 |
| 5 | 42 |
| 6 | 133 |
| 7 | 442 |
| 8 | 1535 |
| 9 | 5546 |
| 10 | 20754 |
| 11 | 80113 |
| 12 | 317875 |
| 13 | 1292648 |
| 14 | 5374073 |
| 15 | 22794182 |
| 16 | 98462847 |
| 17 | 432498659 |
| 18 | 1929221610 |
| 19 | 8728815103 |
| 20 | 40017844229 |
| 21 | 185727603829 |
| 22 | 871897549029 |
| 23 | 4137132922197 |
| 24 | 19828476952117 |
| 25 | 95934298966615 |
| 26 | 468291607852143 |
| 27 | 2305162065138433 |