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 | 3 |
| 3 | 6 |
| 4 | 13 |
| 5 | 25 |
| 6 | 58 |
| 7 | 121 |
| 8 | 283 |
| 9 | 646 |
| 10 | 1527 |
| 11 | 3601 |
| 12 | 8678 |
| 13 | 20881 |
| 14 | 50823 |
| 15 | 124054 |
| 16 | 304573 |
| 17 | 750121 |
| 18 | 1855098 |
| 19 | 4600201 |
| 20 | 11442085 |
| 21 | 28527446 |
| 22 | 71292603 |
| 23 | 178526881 |
| 24 | 447919418 |
| 25 | 1125750145 |
| 26 | 2833906683 |
| 27 | 7144450566 |
| 28 | 18036423973 |