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 | 49 |
| 2 | 1176 |
| 3 | 18424 |
| 4 | 211876 |
| 5 | 1906884 |
| 6 | 13983816 |
| 7 | 85900584 |
| 8 | 450978066 |
| 9 | 2054455634 |
| 10 | 8217822536 |
| 11 | 29135916264 |
| 12 | 92263734836 |
| 13 | 262596783764 |
| 14 | 675248872536 |
| 15 | 1575580702584 |
| 16 | 3348108992991 |
| 17 | 6499270398159 |
| 18 | 11554258485616 |
| 19 | 18851684897584 |
| 20 | 28277527346376 |