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 | 2 |
| 3 | 4 |
| 4 | 10 |
| 5 | 23 |
| 6 | 63 |
| 7 | 155 |
| 8 | 448 |
| 9 | 1152 |
| 10 | 3452 |
| 11 | 9158 |
| 12 | 28177 |
| 13 | 76537 |
| 14 | 240343 |
| 15 | 665073 |
| 16 | 2122968 |
| 17 | 5963685 |
| 18 | 19295541 |
| 19 | 54883588 |
| 20 | 179608831 |
| 21 | 516272903 |
| 22 | 1706070421 |
| 23 | 4948280698 |
| 24 | 16490889347 |
| 25 | 48203859456 |
| 26 | 161842379157 |
| 27 | 476304741819 |
| 28 | 1609703418480 |
| 29 | 4765887074059 |
| 30 | 16201200791291 |