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) |
|---|---|
| 2 | 2 |
| 3 | 6 |
| 4 | 22 |
| 5 | 101 |
| 6 | 546 |
| 7 | 3502 |
| 8 | 25586 |
| 9 | 214062 |
| 10 | 1987516 |
| 11 | 20599076 |
| 12 | 232482372 |
| 13 | 2876191276 |
| 14 | 38228128472 |
| 15 | 549706132536 |
| 16 | 8408517839416 |
| 17 | 137788390312712 |
| 18 | 2383879842920976 |
| 19 | 43846851982943152 |
| 20 | 846470648320690736 |
| 21 | 17266870434276713616 |
| 22 | 367937854493289655072 |