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 | 1 |
| 2 | 0 |
| 3 | 1 |
| 4 | 1 |
| 5 | 2 |
| 6 | 4 |
| 7 | 7 |
| 8 | 16 |
| 9 | 41 |
| 10 | 108 |
| 11 | 320 |
| 12 | 1042 |
| 13 | 3575 |
| 14 | 13064 |
| 15 | 49938 |
| 16 | 197729 |
| 17 | 805991 |
| 18 | 3363084 |
| 19 | 14302891 |
| 20 | 61813285 |
| 21 | 270805177 |
| 22 | 1200460492 |
| 23 | 5376709415 |
| 24 | 24302430375 |
| 25 | 110745093999 |
| 26 | 508380790741 |