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 | 16 |
| 3 | 77 |
| 4 | 256 |
| 5 | 1104 |
| 6 | 4121 |
| 7 | 16832 |
| 8 | 65536 |
| 9 | 264688 |
| 10 | 1048617 |
| 11 | 4205568 |
| 12 | 16779008 |
| 13 | 67162112 |
| 14 | 268436016 |
| 15 | 1073999165 |
| 16 | 4294967296 |
| 17 | 17180983296 |
| 18 | 68719549696 |
| 19 | 274882887680 |
| 20 | 1099511628896 |
| 21 | 4398068904021 |
| 22 | 17592186086656 |
| 23 | 70368840646656 |
| 24 | 281474978676736 |
| 25 | 1125900326286464 |