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) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 1 |
| 4 | 1 |
| 5 | 43 |
| 6 | 3 |
| 7 | 197 |
| 8 | 499 |
| 9 | 5471 |
| 10 | 589 |
| 11 | 82609 |
| 12 | 7243 |
| 13 | 1376527 |
| 14 | 1530967 |
| 15 | 1687123 |
| 16 | 217033 |
| 17 | 68127937 |
| 18 | 1290761 |
| 19 | 500679401 |
| 20 | 107119657 |
| 21 | 38046795 |
| 22 | 1756445 |
| 23 | 983477669 |
| 24 | 622806889 |
| 25 | 81955769933 |
| 26 | 86074407533 |
| 27 | 811851812797 |
| 28 | 29280696293 |