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 | 0 |
| 2 | 1 |
| 3 | 0 |
| 4 | 3 |
| 5 | 2 |
| 6 | 12 |
| 7 | 14 |
| 8 | 54 |
| 9 | 86 |
| 10 | 274 |
| 11 | 528 |
| 12 | 1515 |
| 13 | 3266 |
| 14 | 8854 |
| 15 | 20422 |
| 16 | 53786 |
| 17 | 129368 |
| 18 | 336103 |
| 19 | 830148 |
| 20 | 2145020 |
| 21 | 5390580 |
| 22 | 13913325 |
| 23 | 35378586 |
| 24 | 91415954 |
| 25 | 234397542 |
| 26 | 606983495 |
| 27 | 1566013450 |
| 28 | 4065765499 |
| 29 | 10540066710 |
| 30 | 27437831060 |
| 31 | 71404804002 |