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 | 0 |
| 3 | 2 |
| 4 | 2 |
| 5 | 0 |
| 6 | 0 |
| 7 | 8 |
| 8 | 14 |
| 9 | 0 |
| 10 | 0 |
| 11 | 70 |
| 12 | 124 |
| 13 | 0 |
| 14 | 0 |
| 15 | 722 |
| 16 | 1314 |
| 17 | 0 |
| 18 | 0 |
| 19 | 8220 |
| 20 | 15272 |
| 21 | 0 |
| 22 | 0 |
| 23 | 99820 |
| 24 | 187692 |
| 25 | 0 |
| 26 | 0 |
| 27 | 1265204 |
| 28 | 2399784 |
| 29 | 0 |
| 30 | 0 |
| 31 | 16547220 |
| 32 | 31592878 |
| 33 | 0 |
| 34 | 0 |
| 35 | 221653776 |
| 36 | 425363952 |
| 37 | 0 |
| 38 | 0 |
| 39 | 3025553180 |
| 40 | 5830034720 |
| 41 | 0 |
| 42 | 0 |
| 43 | 41931984034 |
| 44 | 81072032060 |
| 45 | 0 |
| 46 | 0 |