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 | 22 |
| 4 | 66 |
| 5 | 222 |
| 6 | 862 |
| 7 | 3838 |
| 8 | 19542 |
| 9 | 111894 |
| 10 | 712282 |
| 11 | 4987672 |
| 12 | 38102844 |
| 13 | 315339898 |
| 14 | 2810523166 |
| 15 | 26838510154 |
| 16 | 273374835624 |
| 17 | 2958608945772 |
| 18 | 33903161435148 |
| 19 | 410085034127000 |
| 20 | 5221364826476796 |
| 21 | 69804505809732988 |