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 | 4 |
| 2 | 5 |
| 3 | 31 |
| 4 | 247 |
| 5 | 389 |
| 6 | 1307 |
| 7 | 15637 |
| 8 | 13327 |
| 9 | 187111 |
| 10 | 199123 |
| 11 | 353201 |
| 12 | 6364777 |
| 13 | 127056883 |
| 14 | 23083451 |
| 15 | 24191987 |
| 16 | 579694957 |
| 17 | 535076383 |
| 18 | 13912332463 |
| 19 | 43224283189 |
| 20 | 40355946289 |
| 21 | 1210479158981 |
| 22 | 38689398709811 |
| 23 | 72866186391697 |
| 24 | 75054119011297 |
| 25 | 77117026909777 |
| 26 | 73105817107177 |
| 27 | 2777117009412349 |