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 | 3 |
| 2 | 4 |
| 3 | 4 |
| 4 | 41 |
| 5 | 41 |
| 6 | 47 |
| 7 | 47 |
| 8 | 289 |
| 9 | 289 |
| 10 | 1502 |
| 11 | 1502 |
| 12 | 15551 |
| 13 | 15551 |
| 14 | 5809 |
| 15 | 5809 |
| 16 | 3818123 |
| 17 | 3818123 |
| 18 | -76776508 |
| 19 | -76776508 |
| 20 | 934336415 |
| 21 | 934336415 |
| 22 | -127396984577 |
| 23 | -127396984577 |
| 24 | 6013822435553 |
| 25 | 6013822435553 |
| 26 | -149990624319638 |
| 27 | -149990624319638 |
| 28 | 167911724519886437 |
| 29 | 167911724519886437 |