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 | 4 |
| 2 | 12 |
| 3 | 40 |
| 4 | 176 |
| 5 | 724 |
| 6 | 3276 |
| 7 | 14620 |
| 8 | 61044 |
| 9 | 250396 |
| 10 | 1012804 |
| 11 | 4076236 |
| 12 | 16344284 |
| 13 | 65471860 |
| 14 | 262071708 |
| 15 | 1048641260 |