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 | 1 |
| 1 | 4 |
| 2 | 9 |
| 3 | 18 |
| 4 | 35 |
| 5 | 68 |
| 6 | 133 |
| 7 | 262 |
| 8 | 519 |
| 9 | 1032 |
| 10 | 2057 |
| 11 | 4106 |
| 12 | 8203 |
| 13 | 16396 |
| 14 | 32781 |
| 15 | 65550 |
| 16 | 131087 |
| 17 | 262160 |
| 18 | 524305 |
| 19 | 1048594 |
| 20 | 2097171 |
| 21 | 4194324 |
| 22 | 8388629 |
| 23 | 16777238 |
| 24 | 33554455 |
| 25 | 67108888 |
| 26 | 134217753 |
| 27 | 268435482 |
| 28 | 536870939 |
| 29 | 1073741852 |
| 30 | 2147483677 |
| 31 | 4294967326 |
| 32 | 8589934623 |
| 33 | 17179869216 |