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 | 0 |
| 1 | 1 |
| 2 | 1 |
| 3 | 9 |
| 4 | 25 |
| 5 | 121 |
| 6 | 441 |
| 7 | 1849 |
| 8 | 7225 |
| 9 | 29241 |
| 10 | 116281 |
| 11 | 466489 |
| 12 | 1863225 |
| 13 | 7458361 |
| 14 | 29822521 |
| 15 | 119311929 |
| 16 | 477204025 |
| 17 | 1908903481 |
| 18 | 7635439161 |
| 19 | 30542106169 |
| 20 | 122167725625 |
| 21 | 488672300601 |
| 22 | 1954686406201 |
| 23 | 7818751217209 |
| 24 | 31274993684025 |