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 | 2 |
| 1 | -4 |
| 2 | 8 |
| 3 | -12 |
| 4 | 24 |
| 5 | -32 |
| 6 | 64 |
| 7 | -68 |
| 8 | 152 |
| 9 | -120 |
| 10 | 392 |
| 11 | -124 |
| 12 | 1000 |
| 13 | 320 |
| 14 | 3056 |
| 15 | 2836 |
| 16 | 10280 |
| 17 | 15112 |
| 18 | 38668 |
| 19 | 68348 |
| 20 | 154152 |
| 21 | 297948 |
| 22 | 633352 |
| 23 | 1269884 |
| 24 | 2649892 |
| 25 | 5395272 |
| 26 | 11157512 |
| 27 | 22890976 |
| 28 | 47251564 |
| 29 | 97224304 |
| 30 | 200605456 |
| 31 | 413622556 |
| 32 | 853809232 |
| 33 | 1762332664 |
| 34 | 3640315888 |
| 35 | 7521114700 |
| 36 | 15545862696 |
| 37 | 32142131064 |
| 38 | 66481012488 |
| 39 | 137544496052 |