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 | 0 |
| 3 | 0 |
| 4 | 1 |
| 5 | 0 |
| 6 | 1 |
| 7 | 1 |
| 8 | 7 |
| 9 | 37 |
| 10 | 22 |
| 11 | 264 |
| 12 | 310 |
| 13 | 1181 |
| 14 | 2350 |
| 15 | 8102 |
| 16 | 38471 |
| 17 | 136528 |
| 18 | 738072 |
| 19 | 2811383 |
| 20 | 12163208 |
| 21 | 45121906 |
| 22 | 160620225 |
| 23 | 729516611 |
| 24 | 3962353196 |