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 | 0 |
| 1 | 1 |
| 2 | 3 |
| 3 | 6 |
| 4 | 16 |
| 5 | 33 |
| 6 | 91 |
| 7 | 190 |
| 8 | 528 |
| 9 | 1105 |
| 10 | 3075 |
| 11 | 6438 |
| 12 | 17920 |
| 13 | 37521 |
| 14 | 104443 |
| 15 | 218686 |
| 16 | 608736 |
| 17 | 1274593 |
| 18 | 3547971 |
| 19 | 7428870 |
| 20 | 20679088 |
| 21 | 43298625 |
| 22 | 120526555 |
| 23 | 252362878 |
| 24 | 702480240 |
| 25 | 1470878641 |
| 26 | 4094354883 |
| 27 | 8572908966 |
| 28 | 23863649056 |
| 29 | 49966575153 |
| 30 | 139087539451 |