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 | 2 |
| 2 | 4 |
| 3 | 8 |
| 4 | 17 |
| 5 | 40 |
| 6 | 106 |
| 7 | 307 |
| 8 | 927 |
| 9 | 2818 |
| 10 | 8480 |
| 11 | 25142 |
| 12 | 73555 |
| 13 | 213204 |
| 14 | 615074 |
| 15 | 1773036 |
| 16 | 5121195 |
| 17 | 14843518 |
| 18 | 43190084 |
| 19 | 126112096 |
| 20 | 369264395 |
| 21 | 1083378784 |
| 22 | 3182684838 |
| 23 | 9357797643 |
| 24 | 27529874201 |
| 25 | 81028448678 |
| 26 | 238599098824 |
| 27 | 702932296258 |
| 28 | 2072003987285 |
| 29 | 6111009331876 |