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 | 7 |
| 2 | 50 |
| 3 | 363 |
| 4 | 2669 |
| 5 | 19814 |
| 6 | 148153 |
| 7 | 1113615 |
| 8 | 8402722 |
| 9 | 63577171 |
| 10 | 481991621 |
| 11 | 3659227062 |
| 12 | 27808295345 |
| 13 | 211479529943 |
| 14 | 1609093780114 |
| 15 | 12247558413819 |
| 16 | 93245414394973 |
| 17 | 710040492168070 |
| 18 | 5407464407991017 |
| 19 | 41185377124992351 |
| 20 | 313703861897268866 |
| 21 | 2389549742539808867 |