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 | 3 |
| 2 | 8 |
| 3 | 23 |
| 4 | 66 |
| 5 | 188 |
| 6 | 537 |
| 7 | 1533 |
| 8 | 4376 |
| 9 | 12493 |
| 10 | 35664 |
| 11 | 101812 |
| 12 | 290649 |
| 13 | 829731 |
| 14 | 2368680 |
| 15 | 6762003 |
| 16 | 19303866 |
| 17 | 55107824 |
| 18 | 157319377 |
| 19 | 449108397 |
| 20 | 1282094784 |
| 21 | 3660067465 |
| 22 | 10448598672 |
| 23 | 29828197224 |
| 24 | 85152217777 |
| 25 | 243088784019 |
| 26 | 693959105912 |
| 27 | 1981083753503 |
| 28 | 5655510252642 |