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 | 2 |
| 2 | 1 |
| 3 | 2 |
| 4 | 1 |
| 5 | 3 |
| 6 | -1 |
| 7 | 6 |
| 8 | -7 |
| 9 | 19 |
| 10 | -33 |
| 11 | 73 |
| 12 | -146 |
| 13 | 311 |
| 14 | -652 |
| 15 | 1392 |
| 16 | -2977 |
| 17 | 6420 |
| 18 | -13899 |
| 19 | 30247 |
| 20 | -66078 |
| 21 | 144911 |
| 22 | -318853 |
| 23 | 703768 |
| 24 | -1557718 |
| 25 | 3456813 |
| 26 | -7689531 |
| 27 | 17142887 |
| 28 | -38296408 |
| 29 | 85715645 |
| 30 | -192191445 |
| 31 | 431647744 |
| 32 | -970958480 |
| 33 | 2187288804 |
| 34 | -4934101775 |
| 35 | 11144794835 |
| 36 | -25203825094 |