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) |
|---|---|
| 1 | 4 |
| 2 | 6 |
| 3 | 10 |
| 4 | 18 |
| 5 | 35 |
| 6 | 69 |
| 7 | 136 |
| 8 | 270 |
| 9 | 539 |
| 10 | 1077 |
| 11 | 2152 |
| 12 | 4303 |
| 13 | 8605 |
| 14 | 17208 |
| 15 | 34415 |
| 16 | 68829 |
| 17 | 137657 |
| 18 | 275313 |
| 19 | 550625 |
| 20 | 1101249 |
| 21 | 2202497 |
| 22 | 4404993 |
| 23 | 8809985 |
| 24 | 17619969 |
| 25 | 35239936 |
| 26 | 70479871 |
| 27 | 140959741 |
| 28 | 281919481 |
| 29 | 563838961 |
| 30 | 1127677921 |
| 31 | 2255355841 |