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 | 0 |
| 1 | -2 |
| 2 | -8 |
| 3 | -28 |
| 4 | -96 |
| 5 | -328 |
| 6 | -1120 |
| 7 | -3824 |
| 8 | -13056 |
| 9 | -44576 |
| 10 | -152192 |
| 11 | -519616 |
| 12 | -1774080 |
| 13 | -6057088 |
| 14 | -20680192 |
| 15 | -70606592 |
| 16 | -241065984 |
| 17 | -823050752 |
| 18 | -2810071040 |
| 19 | -9594182656 |
| 20 | -32756588544 |
| 21 | -111837988864 |
| 22 | -381838778368 |
| 23 | -1303679135744 |
| 24 | -4451038986240 |
| 25 | -15196797673472 |