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 | 0 |
| 5 | 655 |
| 6 | 26952 |
| 7 | 309869 |
| 8 | 1998752 |
| 9 | 9124848 |
| 10 | 33065040 |
| 11 | 101473009 |
| 12 | 274593648 |
| 13 | 673080928 |
| 14 | 1522931256 |
| 15 | 3224953725 |
| 16 | 6458355776 |
| 17 | 12330557912 |
| 18 | 22588294464 |
| 19 | 39908439249 |
| 20 | 68290845520 |
| 21 | 113579839128 |
| 22 | 184145882536 |
| 23 | 291764365485 |
| 24 | 452734505952 |
| 25 | 689287992800 |