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 | 0 |
| 2 | 13 |
| 3 | 35 |
| 4 | 169 |
| 5 | 651 |
| 6 | 2715 |
| 7 | 11011 |
| 8 | 45099 |
| 9 | 184063 |
| 10 | 752155 |
| 11 | 3072247 |
| 12 | 12550859 |
| 13 | 51270383 |
| 14 | 209444163 |
| 15 | 855592375 |
| 16 | 3495156539 |
| 17 | 14277953839 |
| 18 | 58326437619 |
| 19 | 238267540647 |
| 20 | 973339457803 |
| 21 | 3976159254687 |
| 22 | 16242886662499 |
| 23 | 66353319815959 |
| 24 | 271057918757755 |
| 25 | 1107290419059023 |