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 | 2 |
| 2 | 6 |
| 3 | 16 |
| 4 | 38 |
| 5 | 84 |
| 6 | 178 |
| 7 | 368 |
| 8 | 750 |
| 9 | 1516 |
| 10 | 3050 |
| 11 | 6120 |
| 12 | 12262 |
| 13 | 24548 |
| 14 | 49122 |
| 15 | 98272 |
| 16 | 196574 |
| 17 | 393180 |
| 18 | 786394 |
| 19 | 1572824 |
| 20 | 3145686 |
| 21 | 6291412 |
| 22 | 12582866 |
| 23 | 25165776 |
| 24 | 50331598 |
| 25 | 100663244 |
| 26 | 201326538 |
| 27 | 402653128 |
| 28 | 805306310 |
| 29 | 1610612676 |
| 30 | 3221225410 |
| 31 | 6442450880 |
| 32 | 12884901822 |
| 33 | 25769803708 |