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 | 13 |
| 4 | 34 |
| 5 | 88 |
| 6 | 225 |
| 7 | 569 |
| 8 | 1425 |
| 9 | 3538 |
| 10 | 8717 |
| 11 | 21331 |
| 12 | 51879 |
| 13 | 125474 |
| 14 | 301929 |
| 15 | 723144 |
| 16 | 1724532 |
| 17 | 4096210 |
| 18 | 9693455 |
| 19 | 22859524 |
| 20 | 53733252 |
| 21 | 125919189 |
| 22 | 294232580 |
| 23 | 685661202 |
| 24 | 1593719407 |
| 25 | 3695348909 |
| 26 | 8548564856 |
| 27 | 19732115915 |
| 28 | 45450793102 |
| 29 | 104481137953 |
| 30 | 239718272765 |