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 | 5 |
| 3 | 11 |
| 4 | 26 |
| 5 | 59 |
| 6 | 137 |
| 7 | 312 |
| 8 | 719 |
| 9 | 1651 |
| 10 | 3816 |
| 11 | 8757 |
| 12 | 20202 |
| 13 | 46440 |
| 14 | 106957 |
| 15 | 245989 |
| 16 | 566561 |
| 17 | 1303968 |
| 18 | 3002247 |
| 19 | 6910122 |
| 20 | 15909143 |