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 | 5 |
| 1 | 27 |
| 2 | 65 |
| 3 | 455 |
| 4 | 1365 |
| 5 | 6827 |
| 6 | 17745 |
| 7 | 121527 |
| 8 | 328965 |
| 9 | 1776411 |
| 10 | 4276545 |
| 11 | 29804231 |
| 12 | 89149525 |
| 13 | 447852971 |
| 14 | 1158943825 |
| 15 | 7976283575 |
| 16 | 21475164165 |
| 17 | 115965886491 |
| 18 | 279177134145 |
| 19 | 1954239939015 |
| 20 | 5862719817045 |