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 | 1 |
| 3 | 0 |
| 4 | 4 |
| 5 | 4 |
| 6 | 14 |
| 7 | 20 |
| 8 | 56 |
| 9 | 98 |
| 10 | 224 |
| 11 | 420 |
| 12 | 902 |
| 13 | 1764 |
| 14 | 3664 |
| 15 | 7258 |
| 16 | 14824 |
| 17 | 29596 |
| 18 | 59942 |
| 19 | 120012 |
| 20 | 241944 |
| 21 | 484946 |
| 22 | 975216 |
| 23 | 1955244 |
| 24 | 3926078 |
| 25 | 7870980 |
| 26 | 15790272 |
| 27 | 31650090 |
| 28 | 63456208 |
| 29 | 127162580 |
| 30 | 254845446 |
| 31 | 510582236 |
| 32 | 1022940392 |
| 33 | 2049048890 |
| 34 | 4104264424 |
| 35 | 8219808108 |