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 | 0 |
| 1 | 1 |
| 2 | 4 |
| 3 | 12 |
| 4 | 37 |
| 5 | 111 |
| 6 | 333 |
| 7 | 1000 |
| 8 | 3001 |
| 9 | 9003 |
| 10 | 27009 |
| 11 | 81028 |
| 12 | 243084 |
| 13 | 729253 |
| 14 | 2187760 |
| 15 | 6563280 |
| 16 | 19689841 |
| 17 | 59069523 |
| 18 | 177208569 |
| 19 | 531625708 |
| 20 | 1594877124 |
| 21 | 4784631373 |
| 22 | 14353894120 |
| 23 | 43061682360 |
| 24 | 129185047080 |
| 25 | 387555141241 |
| 26 | 1162665423724 |