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 | 13 |
| 2 | 91 |
| 3 | 257 |
| 4 | 1775 |
| 5 | 7369 |
| 6 | 49747 |
| 7 | 262925 |
| 8 | 1763151 |
| 9 | 10536621 |
| 10 | 70819767 |
| 11 | 449413269 |
| 12 | 3032790187 |
| 13 | 19849674769 |
| 14 | 134432007295 |
| 15 | 895147297233 |
| 16 | 6080318813363 |
| 17 | 40910518802585 |
| 18 | 278583012405979 |
| 19 | 1887082800975125 |
| 20 | 12878423767271251 |