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 | 1 |
| 2 | 25 |
| 3 | 425 |
| 4 | 7025 |
| 5 | 116625 |
| 6 | 1951625 |
| 7 | 32903225 |
| 8 | 558265825 |
| 9 | 9522632225 |
| 10 | 163160773625 |
| 11 | 2806202183625 |
| 12 | 48420275891025 |
| 13 | 837813745045425 |
| 14 | 14531896733426025 |
| 15 | 252593595973313625 |
| 16 | 4398859688478578625 |
| 17 | 76733590756134492225 |
| 18 | 1340547988367851940825 |
| 19 | 23451231922182584693225 |