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) |
|---|---|
| 2 | 2 |
| 3 | 6 |
| 4 | 18 |
| 5 | 46 |
| 6 | 107 |
| 7 | 235 |
| 8 | 498 |
| 9 | 1032 |
| 10 | 2109 |
| 11 | 4273 |
| 12 | 8612 |
| 13 | 17302 |
| 14 | 34695 |
| 15 | 69495 |
| 16 | 139110 |
| 17 | 278356 |
| 18 | 556865 |
| 19 | 1113901 |
| 20 | 2227992 |
| 21 | 4456194 |
| 22 | 8912619 |
| 23 | 17825491 |
| 24 | 35651258 |
| 25 | 71302816 |
| 26 | 142605957 |
| 27 | 285212265 |
| 28 | 570424908 |
| 29 | 1140850222 |
| 30 | 2281700879 |