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 | 32 |
| 5 | 93 |
| 6 | 272 |
| 7 | 807 |
| 8 | 2404 |
| 9 | 7185 |
| 10 | 21516 |
| 11 | 64483 |
| 12 | 193352 |
| 13 | 579909 |
| 14 | 1739496 |
| 15 | 5218143 |
| 16 | 15653900 |
| 17 | 46960889 |
| 18 | 140881444 |
| 19 | 422642459 |
| 20 | 1267924528 |
| 21 | 3803769261 |
| 22 | 11411301184 |
| 23 | 34233893527 |
| 24 | 102701665332 |
| 25 | 308104972769 |
| 26 | 924314883004 |
| 27 | 2772944595283 |
| 28 | 8318833704088 |
| 29 | 24956500987925 |