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 | 28 |
| 3 | 225 |
| 4 | 1540 |
| 5 | 10217 |
| 6 | 67388 |
| 7 | 444017 |
| 8 | 2925140 |
| 9 | 19270105 |
| 10 | 126946444 |
| 11 | 836290209 |
| 12 | 5509263332 |
| 13 | 36293601737 |
| 14 | 239092863324 |
| 15 | 1575081964113 |
| 16 | 10376232739316 |
| 17 | 68355938510649 |
| 18 | 450311249502892 |
| 19 | 2966534083948417 |
| 20 | 19542759549039748 |
| 21 | 128742647137776169 |
| 22 | 848123272992954492 |