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 | 11 |
| 3 | 40 |
| 4 | 149 |
| 5 | 564 |
| 6 | 2166 |
| 7 | 8420 |
| 8 | 33074 |
| 9 | 131085 |
| 10 | 523599 |
| 11 | 2105727 |
| 12 | 8519469 |
| 13 | 34652696 |
| 14 | 141621164 |
| 15 | 581266730 |
| 16 | 2394961851 |
| 17 | 9902433681 |
| 18 | 41074316737 |
| 19 | 170869972460 |
| 20 | 712729001716 |
| 21 | 2980264528670 |
| 22 | 12490379959184 |
| 23 | 52458339164169 |