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) |
|---|---|
| 1 | 0 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 0 |
| 6 | -3 |
| 7 | -9 |
| 8 | -19 |
| 9 | -32 |
| 10 | -43 |
| 11 | -39 |
| 12 | 5 |
| 13 | 128 |
| 14 | 377 |
| 15 | 783 |
| 16 | 1305 |
| 17 | 1728 |
| 18 | 1513 |
| 19 | -367 |
| 20 | -5495 |
| 21 | -15744 |
| 22 | -32267 |
| 23 | -53177 |
| 24 | -69371 |
| 25 | -58464 |
| 26 | 21693 |
| 27 | 235305 |
| 28 | 656909 |
| 29 | 1328896 |
| 30 | 2165489 |
| 31 | 2781855 |
| 32 | 2249009 |
| 33 | -1161856 |
| 34 | -10052911 |
| 35 | -27385695 |
| 36 | -54696687 |
| 37 | -88125696 |
| 38 | -111427091 |
| 39 | -86075113 |
| 40 | 58797853 |
| 41 | 428575584 |
| 42 | 1140728485 |
| 43 | 2249936377 |