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 | 5 |
| 2 | 25 |
| 3 | 25 |
| 4 | 625 |
| 5 | 3125 |
| 6 | 15625 |
| 7 | 78125 |
| 8 | 3125 |
| 9 | 1953125 |
| 10 | 9765625 |
| 11 | 48828125 |
| 12 | 244140625 |
| 13 | 244140625 |
| 14 | 1220703125 |
| 15 | 6103515625 |
| 16 | 30517578125 |
| 17 | 152587890625 |
| 18 | 152587890625 |
| 19 | 3814697265625 |
| 20 | 19073486328125 |