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 | 3 |
| 3 | 6 |
| 4 | 11 |
| 5 | 26 |
| 6 | 58 |
| 7 | 142 |
| 8 | 351 |
| 9 | 890 |
| 10 | 2282 |
| 11 | 5948 |
| 12 | 15624 |
| 13 | 41442 |
| 14 | 110703 |
| 15 | 297676 |
| 16 | 804892 |
| 17 | 2187490 |
| 18 | 5971392 |
| 19 | 16366734 |
| 20 | 45021391 |
| 21 | 124253828 |
| 22 | 343956858 |
| 23 | 954760502 |
| 24 | 2656946827 |
| 25 | 7411140120 |
| 26 | 20716895918 |
| 27 | 58027609028 |
| 28 | 162837485745 |