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 | 10 |
| 2 | 100 |
| 3 | 370 |
| 4 | 1970 |
| 5 | 9040 |
| 6 | 43990 |
| 7 | 209050 |
| 8 | 1002960 |
| 9 | 4793390 |
| 10 | 22944590 |
| 11 | 109759520 |
| 12 | 525189790 |
| 13 | 2512723030 |
| 14 | 12022412680 |
| 15 | 57521607650 |
| 16 | 275215898890 |
| 17 | 1316784620900 |
| 18 | 6300231318630 |
| 19 | 30143802148430 |
| 20 | 144224703156300 |
| 21 | 690051081572450 |