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 | -1 |
| 2 | -3 |
| 3 | -3 |
| 4 | -1 |
| 5 | 10 |
| 6 | 20 |
| 7 | 36 |
| 8 | 28 |
| 9 | -11 |
| 10 | -103 |
| 11 | -245 |
| 12 | -397 |
| 13 | -448 |
| 14 | -214 |
| 15 | 464 |
| 16 | 1817 |
| 17 | 3680 |
| 18 | 5660 |
| 19 | 6473 |
| 20 | 4362 |
| 21 | -3232 |
| 22 | -18428 |
| 23 | -41946 |
| 24 | -70589 |
| 25 | -94890 |
| 26 | -96996 |
| 27 | -49673 |
| 28 | 78907 |
| 29 | 317995 |
| 30 | 673299 |
| 31 | 1105044 |
| 32 | 1491333 |
| 33 | 1605102 |
| 34 | 1094914 |
| 35 | -479358 |
| 36 | -3561322 |
| 37 | -8404118 |
| 38 | -14781724 |
| 39 | -21595744 |
| 40 | -26450603 |
| 41 | -25329527 |