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 | 58 |
| 2 | 877 |
| 3 | 8030 |
| 4 | 56285 |
| 5 | 335162 |
| 6 | 1792749 |
| 7 | 8904486 |
| 8 | 41949645 |
| 9 | 190129090 |
| 10 | 837258109 |
| 11 | 3607669966 |
| 12 | 15289404989 |
| 13 | 63975698570 |
| 14 | 265065915725 |
| 15 | 1089837752118 |
| 16 | 4454225465325 |
| 17 | 18119738464530 |
| 18 | 73441531708765 |
| 19 | 296814738679390 |
| 20 | 1196884383319261 |
| 21 | 4817845684107098 |