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 | 2 |
| 3 | 12 |
| 4 | 36 |
| 5 | 125 |
| 6 | 384 |
| 7 | 1183 |
| 8 | 3528 |
| 9 | 10404 |
| 10 | 30250 |
| 11 | 87131 |
| 12 | 248832 |
| 13 | 705757 |
| 14 | 1989806 |
| 15 | 5581500 |
| 16 | 15586704 |
| 17 | 43356953 |
| 18 | 120187008 |
| 19 | 332134459 |
| 20 | 915304500 |
| 21 | 2516113236 |
| 22 | 6900949462 |
| 23 | 18888143927 |
| 24 | 51599794176 |
| 25 | 140718765625 |
| 26 | 383142771674 |
| 27 | 1041660829548 |
| 28 | 2828107288188 |
| 29 | 7668512468789 |