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 | 390 |
| 4 | 1215 |
| 5 | 4690 |
| 6 | 16830 |
| 7 | 65765 |
| 8 | 251160 |
| 9 | 994050 |
| 10 | 3911375 |
| 11 | 15639390 |
| 12 | 62524602 |
| 13 | 251961125 |
| 14 | 1016913820 |
| 15 | 4122470862 |
| 16 | 16742504735 |
| 17 | 68184829338 |
| 18 | 278147046150 |
| 19 | 1136817652005 |
| 20 | 4652769761136 |
| 21 | 19069624615146 |
| 22 | 78246585726191 |