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) |
|---|---|
| 1 | 6 |
| 2 | 31 |
| 3 | 140 |
| 4 | 566 |
| 5 | 2104 |
| 6 | 7364 |
| 7 | 24720 |
| 8 | 80196 |
| 9 | 253072 |
| 10 | 780902 |
| 11 | 2365772 |
| 12 | 7058469 |
| 13 | 20789082 |
| 14 | 60560175 |
| 15 | 174763208 |
| 16 | 500245052 |
| 17 | 1421824896 |
| 18 | 4016278792 |
| 19 | 11283371280 |
| 20 | 31547434008 |
| 21 | 87827653936 |
| 22 | 243578509132 |
| 23 | 673221043496 |