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 | 36 |
| 4 | 192 |
| 5 | 1089 |
| 6 | 6642 |
| 7 | 42129 |
| 8 | 275571 |
| 9 | 1844028 |
| 10 | 12567762 |
| 11 | 86924745 |
| 12 | 608612814 |
| 13 | 4305284400 |
| 14 | 30723593751 |
| 15 | 220917003516 |
| 16 | 1599013642359 |
| 17 | 11641144003245 |
| 18 | 85186969539435 |
| 19 | 626245146267393 |
| 20 | 4622806865390823 |
| 21 | 34251800667936939 |
| 22 | 254640579219212457 |