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 | 0 |
| 3 | 0 |
| 4 | 39 |
| 5 | 792 |
| 6 | 7587 |
| 7 | 43836 |
| 8 | 194013 |
| 9 | 696765 |
| 10 | 2145687 |
| 11 | 5851044 |
| 12 | 14546412 |
| 13 | 33347130 |
| 14 | 71662911 |
| 15 | 145616964 |
| 16 | 281816991 |
| 17 | 522786390 |
| 18 | 935155011 |
| 19 | 1618729257 |
| 20 | 2722297371 |
| 21 | 4459330956 |
| 22 | 7133246976 |
| 23 | 11168002962 |
| 24 | 17149002624 |
| 25 | 25863493314 |
| 26 | 38369771853 |