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 | 2 |
| 2 | 4 |
| 3 | 12 |
| 4 | 26 |
| 5 | 60 |
| 6 | 144 |
| 7 | 324 |
| 8 | 728 |
| 9 | 1602 |
| 10 | 3576 |
| 11 | 7808 |
| 12 | 17068 |
| 13 | 36908 |
| 14 | 79520 |
| 15 | 170704 |
| 16 | 364794 |
| 17 | 777036 |
| 18 | 1649456 |
| 19 | 3491188 |
| 20 | 7367544 |
| 21 | 15513336 |
| 22 | 32584648 |
| 23 | 68307264 |
| 24 | 142904080 |
| 25 | 298448914 |
| 26 | 622235060 |
| 27 | 1295320004 |
| 28 | 2692583916 |
| 29 | 5589586996 |
| 30 | 11588905844 |
| 31 | 23999052692 |