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 | 0 |
| 2 | 0 |
| 3 | 1 |
| 4 | 3 |
| 5 | 7 |
| 6 | 17 |
| 7 | 37 |
| 8 | 81 |
| 9 | 174 |
| 10 | 372 |
| 11 | 786 |
| 12 | 1650 |
| 13 | 3438 |
| 14 | 7125 |
| 15 | 14666 |
| 16 | 30048 |
| 17 | 61248 |
| 18 | 124439 |
| 19 | 251921 |
| 20 | 508778 |
| 21 | 1025182 |
| 22 | 2062286 |
| 23 | 4142643 |
| 24 | 8312926 |
| 25 | 16667004 |
| 26 | 33395274 |