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 | 3 |
| 4 | 7 |
| 5 | 14 |
| 6 | 35 |
| 7 | 81 |
| 8 | 208 |
| 9 | 517 |
| 10 | 1351 |
| 11 | 3492 |
| 12 | 9261 |
| 13 | 24521 |
| 14 | 65862 |
| 15 | 177247 |
| 16 | 481191 |
| 17 | 1310338 |
| 18 | 3589143 |
| 19 | 9862257 |
| 20 | 27215012 |
| 21 | 75320969 |
| 22 | 209147407 |
| 23 | 582264200 |
| 24 | 1625342649 |
| 25 | 4547350865 |
| 26 | 12750836298 |
| 27 | 35824579355 |
| 28 | 100843670951 |
| 29 | 284361285238 |
| 30 | 803170176715 |