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 | 2 |
| 2 | 1 |
| 3 | 0 |
| 4 | 0 |
| 5 | 0 |
| 6 | 1 |
| 7 | 2 |
| 8 | 6 |
| 9 | 14 |
| 10 | 30 |
| 11 | 62 |
| 12 | 127 |
| 13 | 252 |
| 14 | 493 |
| 15 | 968 |
| 16 | 1860 |
| 17 | 3600 |
| 18 | 6902 |
| 19 | 13286 |
| 20 | 25446 |
| 21 | 48914 |
| 22 | 93775 |
| 23 | 180314 |
| 24 | 346420 |
| 25 | 666996 |
| 26 | 1284318 |
| 27 | 2477328 |
| 28 | 4781007 |
| 29 | 9240012 |
| 30 | 17870709 |
| 31 | 34604066 |
| 32 | 67058880 |
| 33 | 130084990 |
| 34 | 252545160 |
| 35 | 490722342 |