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 | 1 |
| 2 | 30 |
| 3 | 323 |
| 4 | 3110 |
| 5 | 27777 |
| 6 | 237498 |
| 7 | 1977439 |
| 8 | 16202990 |
| 9 | 131490509 |
| 10 | 1060894002 |
| 11 | 8529819531 |
| 12 | 68439823942 |
| 13 | 548461371993 |
| 14 | 4392080943978 |
| 15 | 35156984457463 |
| 16 | 281349668446430 |
| 17 | 2251228221924645 |
| 18 | 18011798305060578 |
| 19 | 144103388698943651 |
| 20 | 1152868080218482102 |
| 21 | 9223130638279472433 |