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 | 16 |
| 3 | 40 |
| 4 | 136 |
| 5 | 304 |
| 6 | 880 |
| 7 | 1768 |
| 8 | 4936 |
| 9 | 9112 |
| 10 | 25216 |
| 11 | 45016 |
| 12 | 121600 |
| 13 | 212944 |
| 14 | 571552 |
| 15 | 982240 |
| 16 | 2616136 |
| 17 | 4456384 |
| 18 | 11785408 |
| 19 | 19922872 |
| 20 | 52402336 |
| 21 | 88076560 |
| 22 | 230641504 |
| 23 | 385875880 |
| 24 | 1006499200 |
| 25 | 1677720304 |
| 26 | 4361862976 |
| 27 | 7247738776 |
| 28 | 18789905872 |
| 29 | 31138512784 |
| 30 | 80529599680 |
| 31 | 133143986056 |
| 32 | 343594756936 |