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 | 1 |
| 2 | 3 |
| 3 | 5 |
| 4 | 15 |
| 5 | 38 |
| 6 | 75 |
| 7 | 190 |
| 8 | 375 |
| 9 | 950 |
| 10 | 1875 |
| 11 | 4750 |
| 12 | 10296 |
| 13 | 23750 |
| 14 | 51480 |
| 15 | 118750 |
| 16 | 257400 |
| 17 | 593750 |
| 18 | 1287000 |
| 19 | 2968750 |
| 20 | 6435000 |
| 21 | 14843750 |
| 22 | 34182196 |
| 23 | 74218750 |
| 24 | 170910980 |
| 25 | 371093750 |
| 26 | 854554900 |
| 27 | 1855468750 |
| 28 | 4272774500 |
| 29 | 9277343750 |
| 30 | 21363872500 |
| 31 | 46386718750 |