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) |
|---|---|
| 3 | 1 |
| 4 | 0 |
| 5 | 0 |
| 6 | 19 |
| 7 | 68 |
| 8 | 110 |
| 9 | 1679 |
| 10 | 11941 |
| 11 | 59470 |
| 12 | 528974 |
| 13 | 4907480 |
| 14 | 36965659 |
| 15 | 370685663 |
| 16 | 4086527638 |
| 17 | 40650345653 |
| 18 | 458464525689 |
| 19 | 5857242113368 |
| 20 | 72283039099029 |
| 21 | 938515852729074 |
| 22 | 13416951764772945 |
| 23 | 194738851363141390 |
| 24 | 2909111655448399908 |
| 25 | 46421744844240409407 |