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 | 2 |
| 3 | 5 |
| 4 | 12 |
| 5 | 31 |
| 6 | 85 |
| 7 | 248 |
| 8 | 762 |
| 9 | 2440 |
| 10 | 8064 |
| 11 | 27300 |
| 12 | 94150 |
| 13 | 329462 |
| 14 | 1166512 |
| 15 | 4170414 |
| 16 | 15031771 |
| 17 | 54559855 |
| 18 | 199236416 |
| 19 | 731434971 |
| 20 | 2697934577 |
| 21 | 9993489968 |
| 22 | 37157691565 |
| 23 | 138633745173 |
| 24 | 518851050388 |
| 25 | 1947388942885 |
| 26 | 7328186394725 |