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 | 3 |
| 1 | 16 |
| 2 | 104 |
| 3 | 736 |
| 4 | 5408 |
| 5 | 40576 |
| 6 | 308864 |
| 7 | 2377216 |
| 8 | 18457088 |
| 9 | 144295936 |
| 10 | 1134209024 |
| 11 | 8952733696 |
| 12 | 70896263168 |
| 13 | 562816516096 |
| 14 | 4476410691584 |
| 15 | 35654557106176 |
| 16 | 284296086683648 |
| 17 | 2268726473261056 |
| 18 | 18115958466412544 |
| 19 | 144724547816390656 |