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 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 1 |
| 6 | 1 |
| 7 | 1 |
| 8 | 1 |
| 9 | 1 |
| 10 | 0 |
| 11 | -5 |
| 12 | -20 |
| 13 | -55 |
| 14 | -125 |
| 15 | -251 |
| 16 | -461 |
| 17 | -791 |
| 18 | -1286 |
| 19 | -2001 |
| 20 | -3001 |
| 21 | -4356 |
| 22 | -6121 |
| 23 | -8281 |
| 24 | -10626 |
| 25 | -12500 |
| 26 | -12340 |
| 27 | -6885 |
| 28 | 10110 |
| 29 | 49875 |
| 30 | 131626 |
| 31 | 286921 |
| 32 | 565781 |
| 33 | 1044971 |
| 34 | 1838626 |
| 35 | 3110751 |
| 36 | 5087561 |
| 37 | 8064366 |
| 38 | 12395461 |
| 39 | 18444251 |
| 40 | 26451625 |
| 41 | 36249035 |
| 42 | 46692715 |
| 43 | 54618710 |