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 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 5 |
| 6 | 5 |
| 7 | 35 |
| 8 | 5 |
| 9 | 35 |
| 10 | 175 |
| 11 | 1925 |
| 12 | 275 |
| 13 | 25025 |
| 14 | 175175 |
| 15 | 125125 |
| 16 | 875875 |
| 17 | 14889875 |
| 18 | 14889875 |
| 19 | 282625 |
| 20 | 1414538125 |
| 21 | 9901766875 |
| 22 | 2222845625 |
| 23 | 2505147019375 |
| 24 | 2505147019375 |
| 25 | 62628675484375 |
| 26 | 116310397328125 |
| 27 | 814172781296875 |