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) |
|---|---|
| 1 | 3 |
| 2 | 9 |
| 3 | 21 |
| 4 | 63 |
| 5 | 189 |
| 6 | 441 |
| 7 | 567 |
| 8 | 693 |
| 9 | 2079 |
| 10 | 4851 |
| 11 | 6237 |
| 12 | 13167 |
| 13 | 39501 |
| 14 | 92169 |
| 15 | 118503 |
| 16 | 276507 |
| 17 | 829521 |
| 18 | 908523 |
| 19 | 2119887 |
| 20 | 2725569 |
| 21 | 6359661 |
| 22 | 19078983 |
| 23 | 28164213 |
| 24 | 57236949 |
| 25 | 84492639 |
| 26 | 171710847 |
| 27 | 197149491 |
| 28 | 591448473 |
| 29 | 1211061159 |
| 30 | 1774345419 |
| 31 | 3633183477 |
| 32 | 5323036257 |
| 33 | 6505933203 |