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 | 2 |
| 2 | 5 |
| 3 | 27 |
| 4 | 121 |
| 5 | 2037 |
| 6 | 8179 |
| 7 | 131055 |
| 8 | 524269 |
| 9 | 8388585 |
| 10 | 536870883 |
| 11 | 2147483617 |
| 12 | 137438953435 |
| 13 | 2199023255511 |
| 14 | 8796093022165 |
| 15 | 140737488355281 |
| 16 | 9007199254740939 |
| 17 | 576460752303423429 |
| 18 | 2305843009213693891 |