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 | 0 |
| 4 | 1 |
| 5 | 1 |
| 6 | 0 |
| 7 | 0 |
| 8 | 3 |
| 9 | 6 |
| 10 | 3 |
| 11 | 0 |
| 12 | 12 |
| 13 | 36 |
| 14 | 36 |
| 15 | 12 |
| 16 | 55 |
| 17 | 220 |
| 18 | 330 |
| 19 | 220 |
| 20 | 328 |
| 21 | 1365 |
| 22 | 2730 |
| 23 | 2730 |
| 24 | 2793 |
| 25 | 8841 |
| 26 | 21420 |
| 27 | 28560 |
| 28 | 29172 |
| 29 | 62832 |
| 30 | 164220 |
| 31 | 271320 |
| 32 | 314583 |
| 33 | 508896 |
| 34 | 1265628 |
| 35 | 2430480 |
| 36 | 3275085 |
| 37 | 4642803 |
| 38 | 10091664 |
| 39 | 21066804 |
| 40 | 32555028 |
| 41 | 45388200 |
| 42 | 85102875 |