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 | 3 |
| 2 | 12 |
| 3 | 35 |
| 4 | 90 |
| 5 | 217 |
| 6 | 504 |
| 7 | 1143 |
| 8 | 2550 |
| 9 | 5621 |
| 10 | 12276 |
| 11 | 26611 |
| 12 | 57330 |
| 13 | 122865 |
| 14 | 262128 |
| 15 | 557039 |
| 16 | 1179630 |
| 17 | 2490349 |
| 18 | 5242860 |
| 19 | 11010027 |
| 20 | 23068650 |
| 21 | 48234473 |
| 22 | 100663272 |
| 23 | 209715175 |
| 24 | 436207590 |
| 25 | 905969637 |
| 26 | 1879048164 |
| 27 | 3892314083 |
| 28 | 8053063650 |
| 29 | 16642998241 |
| 30 | 34359738336 |