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 | 6 |
| 3 | 16 |
| 4 | 81 |
| 5 | 299 |
| 6 | 1358 |
| 7 | 5567 |
| 8 | 23350 |
| 9 | 91998 |
| 10 | 351058 |
| 11 | 1269907 |
| 12 | 4394634 |
| 13 | 14495236 |
| 14 | 45779246 |
| 15 | 138567568 |
| 16 | 403282017 |
| 17 | 1130773069 |
| 18 | 3062535192 |
| 19 | 8028046724 |
| 20 | 20411824364 |
| 21 | 50429813556 |
| 22 | 121280243676 |
| 23 | 284360432241 |
| 24 | 650972702410 |