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 | 3 |
| 1 | 17 |
| 2 | 129 |
| 3 | 1025 |
| 4 | 8193 |
| 5 | 65537 |
| 6 | 524289 |
| 7 | 4194305 |
| 8 | 33554433 |
| 9 | 268435457 |
| 10 | 2147483649 |
| 11 | 17179869185 |
| 12 | 137438953473 |
| 13 | 1099511627777 |
| 14 | 8796093022209 |
| 15 | 70368744177665 |
| 16 | 562949953421313 |
| 17 | 4503599627370497 |
| 18 | 36028797018963969 |