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 | -8 |
| 2 | 20 |
| 3 | -16 |
| 4 | 2 |
| 5 | 0 |
| 6 | 0 |
| 7 | 0 |
| 8 | -1 |
| 9 | -8 |
| 10 | -44 |
| 11 | -208 |
| 12 | -910 |
| 13 | -3808 |
| 14 | -15504 |
| 15 | -62016 |
| 16 | -245157 |
| 17 | -961400 |
| 18 | -3749460 |
| 19 | -14567280 |
| 20 | -56448210 |
| 21 | -218349120 |
| 22 | -843621600 |
| 23 | -3257112960 |
| 24 | -12570420330 |
| 25 | -48507033744 |
| 26 | -187187399448 |
| 27 | -722477682080 |
| 28 | -2789279908316 |
| 29 | -10772391370048 |