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 | 0 |
| 1 | 0 |
| 2 | 2 |
| 3 | 6 |
| 4 | 20 |
| 5 | 42 |
| 6 | 110 |
| 7 | 210 |
| 8 | 462 |
| 9 | 870 |
| 10 | 1722 |
| 11 | 3080 |
| 12 | 5852 |
| 13 | 10100 |
| 14 | 18090 |
| 15 | 30800 |
| 16 | 53130 |
| 17 | 87912 |
| 18 | 147840 |
| 19 | 239610 |
| 20 | 392502 |
| 21 | 626472 |
| 22 | 1003002 |
| 23 | 1573770 |
| 24 | 2479050 |
| 25 | 3831806 |
| 26 | 5931660 |
| 27 | 9057090 |
| 28 | 13819806 |
| 29 | 20834660 |
| 30 | 31399212 |
| 31 | 46806122 |
| 32 | 69697452 |
| 33 | 102870306 |
| 34 | 151523790 |
| 35 | 221488806 |