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 | 1 |
| 5 | 2 |
| 6 | 0 |
| 7 | 18 |
| 8 | 18 |
| 9 | 18 |
| 10 | 0 |
| 11 | 1606 |
| 12 | 1098 |
| 13 | 684 |
| 14 | 446 |
| 15 | 0 |
| 16 | 565080 |
| 17 | 263580 |
| 18 | 116370 |
| 19 | 55620 |
| 20 | 26430 |
| 21 | 0 |
| 22 | 734774776 |
| 23 | 225806940 |
| 24 | 68822910 |
| 25 | 24578010 |
| 26 | 9729090 |
| 27 | 3596762 |
| 28 | 0 |
| 29 | 3523091615568 |
| 30 | 680637057912 |
| 31 | 136498491360 |
| 32 | 34626926250 |
| 33 | 10819771830 |
| 34 | 3694824126 |
| 35 | 1111506858 |