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 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 1 |
| 6 | 57 |
| 7 | 812 |
| 8 | 6524 |
| 9 | 37309 |
| 10 | 169298 |
| 11 | 648216 |
| 12 | 2176923 |
| 13 | 6582869 |
| 14 | 18262399 |
| 15 | 47129249 |
| 16 | 114344261 |
| 17 | 262987603 |
| 18 | 577216181 |
| 19 | 1215552037 |
| 20 | 2467076907 |
| 21 | 4843870146 |
| 22 | 9229556242 |
| 23 | 17113017451 |
| 24 | 30949065535 |
| 25 | 54705281270 |
| 26 | 94677736245 |
| 27 | 160689668475 |
| 28 | 267828562140 |
| 29 | 438931138500 |