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 | 4 |
| 3 | 11 |
| 4 | 30 |
| 5 | 83 |
| 6 | 236 |
| 7 | 691 |
| 8 | 2050 |
| 9 | 6123 |
| 10 | 18336 |
| 11 | 54971 |
| 12 | 164870 |
| 13 | 494563 |
| 14 | 1483636 |
| 15 | 4450851 |
| 16 | 13352490 |
| 17 | 40057403 |
| 18 | 120172136 |
| 19 | 360516331 |
| 20 | 1081548910 |
| 21 | 3244646643 |
| 22 | 9733939836 |
| 23 | 29201819411 |
| 24 | 87605458130 |
| 25 | 262816374283 |
| 26 | 788449122736 |
| 27 | 2365347368091 |
| 28 | 7096042104150 |