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 | 2 |
| 2 | 4 |
| 3 | 10 |
| 4 | 16 |
| 5 | 34 |
| 6 | 76 |
| 7 | 130 |
| 8 | 256 |
| 9 | 568 |
| 10 | 1036 |
| 11 | 2050 |
| 12 | 4336 |
| 13 | 8194 |
| 14 | 16396 |
| 15 | 33814 |
| 16 | 65536 |
| 17 | 131074 |
| 18 | 266176 |
| 19 | 524290 |
| 20 | 1048816 |
| 21 | 2113462 |
| 22 | 4194316 |
| 23 | 8388610 |
| 24 | 16842496 |
| 25 | 33555424 |
| 26 | 67108876 |
| 27 | 134479360 |
| 28 | 268435696 |
| 29 | 536870914 |
| 30 | 1074793396 |
| 31 | 2147483650 |