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 | 0 |
| 1 | 1 |
| 2 | 4 |
| 3 | 25 |
| 4 | 144 |
| 5 | 841 |
| 6 | 4900 |
| 7 | 28561 |
| 8 | 166464 |
| 9 | 970225 |
| 10 | 5654884 |
| 11 | 32959081 |
| 12 | 192099600 |
| 13 | 1119638521 |
| 14 | 6525731524 |
| 15 | 38034750625 |
| 16 | 221682772224 |
| 17 | 1292061882721 |
| 18 | 7530688524100 |
| 19 | 43892069261881 |
| 20 | 255821727047184 |
| 21 | 1491038293021225 |