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 | 31 |
| 1 | 61 |
| 2 | 121 |
| 3 | 241 |
| 4 | 481 |
| 5 | 961 |
| 6 | 1921 |
| 7 | 3841 |
| 8 | 7681 |
| 9 | 15361 |
| 10 | 30721 |
| 11 | 61441 |
| 12 | 122881 |
| 13 | 245761 |
| 14 | 491521 |
| 15 | 983041 |
| 16 | 1966081 |
| 17 | 3932161 |
| 18 | 7864321 |
| 19 | 15728641 |
| 20 | 31457281 |
| 21 | 62914561 |
| 22 | 125829121 |
| 23 | 251658241 |
| 24 | 503316481 |
| 25 | 1006632961 |
| 26 | 2013265921 |
| 27 | 4026531841 |
| 28 | 8053063681 |
| 29 | 16106127361 |