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 | 8 |
| 2 | 17 |
| 3 | 57 |
| 4 | 177 |
| 5 | 2169 |
| 6 | 8361 |
| 7 | 131361 |
| 8 | 524649 |
| 9 | 8389137 |
| 10 | 536871753 |
| 11 | 2147484609 |
| 12 | 137438954841 |
| 13 | 2199023257233 |
| 14 | 8796093024057 |
| 15 | 140737488357537 |
| 16 | 9007199254743801 |
| 17 | 576460752303426969 |
| 18 | 2305843009213697673 |
| 19 | 147573952589676417417 |
| 20 | 2361183241434822611889 |