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 | 16 |
| 3 | 154 |
| 4 | 1289 |
| 5 | 10180 |
| 6 | 78372 |
| 7 | 596337 |
| 8 | 4512900 |
| 9 | 34064998 |
| 10 | 256825009 |
| 11 | 1935169456 |
| 12 | 14577526976 |
| 13 | 109797758833 |
| 14 | 826945679592 |
| 15 | 6227993359362 |
| 16 | 46904386459065 |
| 17 | 353244994467916 |
| 18 | 2660340755025580 |
| 19 | 20035394638446769 |
| 20 | 150889230111278492 |
| 21 | 1136366561949728110 |