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 | 1 |
| 2 | 11 |
| 3 | 166 |
| 4 | 3091 |
| 5 | 63251 |
| 6 | 1376738 |
| 7 | 31231278 |
| 8 | 730421043 |
| 9 | 17485161178 |
| 10 | 426342182761 |
| 11 | 10551652603526 |
| 12 | 264383070217234 |
| 13 | 6693356751004275 |
| 14 | 170957058318902538 |
| 15 | 4399826606699783666 |
| 16 | 113989308154754290611 |
| 17 | 2970465160237643057033 |
| 18 | 77808659386282667142686 |