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) |
|---|---|
| 2 | 1 |
| 3 | 20 |
| 4 | 307 |
| 5 | 4280 |
| 6 | 56914 |
| 7 | 736568 |
| 8 | 9370183 |
| 9 | 117822512 |
| 10 | 1469283166 |
| 11 | 18210135416 |
| 12 | 224636864830 |
| 13 | 2760899996816 |
| 14 | 33833099832484 |
| 15 | 413610917006000 |
| 16 | 5046403030066927 |
| 17 | 61468359153954656 |
| 18 | 747672504476150374 |
| 19 | 9083423595292949240 |
| 20 | 110239596847544663002 |
| 21 | 1336700736225591436496 |
| 22 | 16195256987701502444284 |