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 | 1 |
| 3 | 2 |
| 4 | 7 |
| 5 | 14 |
| 6 | 30 |
| 7 | 60 |
| 8 | 127 |
| 9 | 254 |
| 10 | 510 |
| 11 | 1020 |
| 12 | 2046 |
| 13 | 4092 |
| 14 | 8188 |
| 15 | 16376 |
| 16 | 32767 |
| 17 | 65534 |
| 18 | 131070 |
| 19 | 262140 |
| 20 | 524286 |
| 21 | 1048572 |
| 22 | 2097148 |
| 23 | 4194296 |
| 24 | 8388606 |
| 25 | 16777212 |
| 26 | 33554428 |
| 27 | 67108856 |
| 28 | 134217724 |
| 29 | 268435448 |
| 30 | 536870904 |
| 31 | 1073741808 |
| 32 | 2147483647 |