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 | 2 |
| 2 | 4 |
| 3 | 9 |
| 4 | 25 |
| 5 | 94 |
| 6 | 520 |
| 7 | 4521 |
| 8 | 64793 |
| 9 | 1581010 |
| 10 | 67106004 |
| 11 | 5029631745 |
| 12 | 673439168257 |
| 13 | 162631617757086 |
| 14 | 71416302988324776 |
| 15 | 57430160224301687377 |
| 16 | 85096038984339418975505 |
| 17 | 233592305902515392375925762 |
| 18 | 1193627868786115606927913952196 |
| 19 | 11402285904243733254203516140245465 |