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 | 2 |
| 3 | 3 |
| 4 | 6 |
| 5 | 12 |
| 6 | 27 |
| 7 | 55 |
| 8 | 115 |
| 9 | 235 |
| 10 | 490 |
| 11 | 994 |
| 12 | 2008 |
| 13 | 4036 |
| 14 | 8120 |
| 15 | 16280 |
| 16 | 32640 |
| 17 | 65344 |
| 18 | 130879 |
| 19 | 261935 |
| 20 | 524057 |
| 21 | 1048301 |
| 22 | 2096855 |
| 23 | 4193951 |
| 24 | 8388239 |
| 25 | 16776799 |
| 26 | 33554339 |
| 27 | 67109539 |
| 28 | 134220995 |