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 | 1 |
| 1 | 12 |
| 2 | 78 |
| 3 | 650 |
| 4 | 5083 |
| 5 | 40690 |
| 6 | 323401 |
| 7 | 2576795 |
| 8 | 20514715 |
| 9 | 163369570 |
| 10 | 1300879372 |
| 11 | 10358963615 |
| 12 | 82488063476 |
| 13 | 656851828075 |
| 14 | 5230500095281 |
| 15 | 41650400765615 |
| 16 | 331661528811227 |
| 17 | 2641015991983270 |
| 18 | 21030372117368865 |
| 19 | 167464549591889570 |
| 20 | 1333517788817519126 |