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 | 1 |
| 3 | 2 |
| 4 | 5 |
| 5 | 151 |
| 6 | 661 |
| 7 | 521 |
| 8 | 49993 |
| 9 | 858868651 |
| 10 | 115523 |
| 11 | 72920757563 |
| 12 | 3844109 |
| 13 | 1637177 |
| 14 | 7158605959 |
| 15 | 17024617 |
| 16 | 13062611 |
| 17 | 66113257898351335849 |
| 18 | 599880481206897379 |
| 19 | 745125370039 |
| 20 | 4314028165895642655831229 |
| 21 | 30699710580827 |
| 22 | 1744795596758086587163381 |
| 23 | 2463356705098399667815003 |