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 | 3 |
| 2 | 11 |
| 3 | 26 |
| 4 | 79 |
| 5 | 224 |
| 6 | 640 |
| 7 | 1828 |
| 8 | 5225 |
| 9 | 14928 |
| 10 | 42654 |
| 11 | 121873 |
| 12 | 348232 |
| 13 | 995003 |
| 14 | 2843014 |
| 15 | 8123337 |
| 16 | 23210809 |
| 17 | 66320216 |
| 18 | 189496620 |
| 19 | 541448364 |
| 20 | 1547079580 |
| 21 | 4420468031 |
| 22 | 12630596045 |
| 23 | 36089381477 |
| 24 | 103118131368 |
| 25 | 294639269914 |
| 26 | 841872308017 |
| 27 | 2405480380385 |
| 28 | 6873175192304 |