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 | 1 |
| 2 | 25 |
| 3 | 121 |
| 4 | 2401 |
| 5 | 10201 |
| 6 | 301401 |
| 7 | 1002001 |
| 8 | 25010001 |
| 9 | 100020001 |
| 10 | 2500100001 |
| 11 | 10000200001 |
| 12 | 250001000001 |
| 13 | 1000002000001 |
| 14 | 25000010000001 |
| 15 | 100000020000001 |
| 16 | 2500000100000001 |
| 17 | 10000000200000001 |
| 18 | 250000001000000001 |