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 | 0 |
| 1 | 1 |
| 2 | 1 |
| 3 | 6 |
| 4 | 9 |
| 5 | 36 |
| 6 | 66 |
| 7 | 218 |
| 8 | 449 |
| 9 | 1332 |
| 10 | 2946 |
| 11 | 8196 |
| 12 | 18954 |
| 13 | 50688 |
| 14 | 120576 |
| 15 | 314586 |
| 16 | 761889 |
| 17 | 1957092 |
| 18 | 4794426 |
| 19 | 12194828 |
| 20 | 30093854 |
| 21 | 76067256 |
| 22 | 188595276 |
| 23 | 474810276 |
| 24 | 1180734234 |
| 25 | 2965094536 |
| 26 | 7387570516 |
| 27 | 18521858088 |
| 28 | 46203981924 |
| 29 | 115721310552 |