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 | 3 |
| 2 | 9 |
| 3 | 27 |
| 4 | 81 |
| 5 | 150 |
| 6 | 366 |
| 7 | 870 |
| 8 | 2022 |
| 9 | 4686 |
| 10 | 10974 |
| 11 | 25614 |
| 12 | 59742 |
| 13 | 139398 |
| 14 | 325350 |
| 15 | 759198 |
| 16 | 1771590 |
| 17 | 4134126 |
| 18 | 9647262 |
| 19 | 22512342 |
| 20 | 52533750 |
| 21 | 122590422 |
| 22 | 286071414 |
| 23 | 667563054 |
| 24 | 1557794622 |
| 25 | 3635198310 |
| 26 | 8482932318 |
| 27 | 19795382454 |
| 28 | 46193598486 |
| 29 | 107795266974 |
| 30 | 251546100558 |
| 31 | 586996465758 |
| 32 | 1369788083022 |