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 | 1 |
| 2 | 4 |
| 3 | 8 |
| 4 | 22 |
| 5 | 52 |
| 6 | 142 |
| 7 | 362 |
| 8 | 973 |
| 9 | 2574 |
| 10 | 6935 |
| 11 | 18643 |
| 12 | 50573 |
| 13 | 137401 |
| 14 | 375306 |
| 15 | 1027898 |
| 16 | 2825831 |
| 17 | 7790055 |
| 18 | 21539352 |
| 19 | 59706865 |
| 20 | 165921896 |
| 21 | 462127857 |
| 22 | 1289901083 |
| 23 | 3607567539 |
| 24 | 10108555623 |
| 25 | 28374358327 |
| 26 | 79777757405 |
| 27 | 224653284863 |