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 | 4 |
| 3 | 17 |
| 4 | 92 |
| 5 | 633 |
| 6 | 5316 |
| 7 | 52609 |
| 8 | 598444 |
| 9 | 7685705 |
| 10 | 109933268 |
| 11 | 1732565841 |
| 12 | 29824133436 |
| 13 | 556682481817 |
| 14 | 11198025452260 |
| 15 | 241481216430113 |
| 16 | 5557135898411468 |
| 17 | 135927902927547369 |
| 18 | 3521462566184392692 |
| 19 | 96323049885512803825 |
| 20 | 2774010846129897006940 |
| 21 | 83898835844633970888761 |