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 | 0 |
| 2 | 1 |
| 3 | 2 |
| 4 | 4 |
| 5 | 8 |
| 6 | 18 |
| 7 | 40 |
| 8 | 100 |
| 9 | 256 |
| 10 | 705 |
| 11 | 2057 |
| 12 | 6370 |
| 13 | 20803 |
| 14 | 71725 |
| 15 | 259678 |
| 16 | 985244 |
| 17 | 3905022 |
| 18 | 16124936 |
| 19 | 69188809 |
| 20 | 307765510 |
| 21 | 1416146859 |
| 22 | 6727549181 |
| 23 | 32938379216 |
| 24 | 165942445714 |
| 25 | 859020421012 |
| 26 | 4563322971706 |
| 27 | 24847598243116 |
| 28 | 138533012486423 |
| 29 | 790075521708603 |
| 30 | 4605183081182354 |