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 | 0 |
| 2 | 3 |
| 3 | 8 |
| 4 | 21 |
| 5 | 48 |
| 6 | 126 |
| 7 | 288 |
| 8 | 693 |
| 9 | 1568 |
| 10 | 3570 |
| 11 | 7896 |
| 12 | 17417 |
| 13 | 37632 |
| 14 | 80823 |
| 15 | 171192 |
| 16 | 359733 |
| 17 | 747936 |
| 18 | 1543192 |
| 19 | 3155760 |
| 20 | 6407037 |
| 21 | 12909024 |
| 22 | 25835649 |
| 23 | 51359136 |
| 24 | 101470854 |
| 25 | 199264128 |
| 26 | 389096028 |
| 27 | 755591256 |
| 28 | 1459643343 |
| 29 | 2805471984 |
| 30 | 5366161740 |
| 31 | 10216161336 |
| 32 | 19362398580 |