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) |
|---|---|
| 2 | 0 |
| 3 | 1 |
| 4 | 1 |
| 5 | 4 |
| 6 | 9 |
| 7 | 22 |
| 8 | 54 |
| 9 | 138 |
| 10 | 346 |
| 11 | 889 |
| 12 | 2285 |
| 13 | 5928 |
| 14 | 15436 |
| 15 | 40424 |
| 16 | 106230 |
| 17 | 280305 |
| 18 | 741912 |
| 19 | 1969816 |
| 20 | 5243942 |
| 21 | 13995807 |
| 22 | 37439883 |
| 23 | 100371907 |
| 24 | 269623436 |
| 25 | 725638613 |
| 26 | 1956352468 |
| 27 | 5283171593 |
| 28 | 14289645110 |
| 29 | 38707131195 |
| 30 | 104995130162 |
| 31 | 285184002486 |
| 32 | 775586517781 |