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 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 3 |
| 4 | 7 |
| 5 | 16 |
| 6 | 43 |
| 7 | 115 |
| 8 | 303 |
| 9 | 813 |
| 10 | 2203 |
| 11 | 5991 |
| 12 | 16371 |
| 13 | 44917 |
| 14 | 123598 |
| 15 | 340988 |
| 16 | 942930 |
| 17 | 2612735 |
| 18 | 7252407 |
| 19 | 20163046 |
| 20 | 56136326 |
| 21 | 156488946 |
| 22 | 436739752 |
| 23 | 1220157514 |
| 24 | 3412116339 |
| 25 | 9550192161 |
| 26 | 26751643663 |
| 27 | 74991516850 |
| 28 | 210364915858 |
| 29 | 590490257667 |
| 30 | 1658484275955 |