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 | 4 |
| 2 | 16 |
| 3 | 64 |
| 4 | 225 |
| 5 | 784 |
| 6 | 2601 |
| 7 | 8464 |
| 8 | 26896 |
| 9 | 84100 |
| 10 | 259081 |
| 11 | 788544 |
| 12 | 2374681 |
| 13 | 7086244 |
| 14 | 20976400 |
| 15 | 61653904 |
| 16 | 180069561 |
| 17 | 522945424 |
| 18 | 1510954641 |
| 19 | 4345446400 |
| 20 | 12444741136 |
| 21 | 35502850084 |
| 22 | 100926300721 |
| 23 | 285976813824 |
| 24 | 807886380625 |
| 25 | 2275928269924 |