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) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 7 |
| 4 | 20 |
| 5 | 49 |
| 6 | 110 |
| 7 | 235 |
| 8 | 488 |
| 9 | 997 |
| 10 | 2018 |
| 11 | 4063 |
| 12 | 8156 |
| 13 | 16345 |
| 14 | 32726 |
| 15 | 65491 |
| 16 | 131024 |
| 17 | 262093 |
| 18 | 524234 |
| 19 | 1048519 |
| 20 | 2097092 |
| 21 | 4194241 |
| 22 | 8388542 |
| 23 | 16777147 |
| 24 | 33554360 |
| 25 | 67108789 |
| 26 | 134217650 |
| 27 | 268435375 |
| 28 | 536870828 |
| 29 | 1073741737 |
| 30 | 2147483558 |