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 | 0 |
| 1 | 0 |
| 2 | 1 |
| 3 | 5 |
| 4 | 18 |
| 5 | 56 |
| 6 | 161 |
| 7 | 443 |
| 8 | 1196 |
| 9 | 3228 |
| 10 | 8823 |
| 11 | 24579 |
| 12 | 69810 |
| 13 | 201380 |
| 14 | 586843 |
| 15 | 1719081 |
| 16 | 5044584 |
| 17 | 14800352 |
| 18 | 43384747 |
| 19 | 127076015 |
| 20 | 372100654 |
| 21 | 1089864344 |
| 22 | 3194496987 |
| 23 | 9372984609 |
| 24 | 27532712140 |
| 25 | 80966582548 |
| 26 | 238342592353 |
| 27 | 702222958797 |
| 28 | 2070454005078 |
| 29 | 6108341367004 |