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 | 0 |
| 1 | 0 |
| 2 | 2 |
| 3 | 5 |
| 4 | 13 |
| 5 | 28 |
| 6 | 60 |
| 7 | 123 |
| 8 | 251 |
| 9 | 506 |
| 10 | 1018 |
| 11 | 2041 |
| 12 | 4089 |
| 13 | 8184 |
| 14 | 16376 |
| 15 | 32759 |
| 16 | 65527 |
| 17 | 131062 |
| 18 | 262134 |
| 19 | 524277 |
| 20 | 1048565 |
| 21 | 2097140 |
| 22 | 4194292 |
| 23 | 8388595 |
| 24 | 16777203 |
| 25 | 33554418 |
| 26 | 67108850 |
| 27 | 134217713 |
| 28 | 268435441 |
| 29 | 536870896 |