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 | 2 |
| 2 | 9 |
| 3 | 34 |
| 4 | 125 |
| 5 | 461 |
| 6 | 1715 |
| 7 | 6434 |
| 8 | 24309 |
| 9 | 92377 |
| 10 | 352715 |
| 11 | 1352077 |
| 12 | 5200299 |
| 13 | 20058299 |
| 14 | 77558759 |
| 15 | 300540194 |
| 16 | 1166803109 |
| 17 | 4537567649 |
| 18 | 17672631899 |
| 19 | 68923264409 |
| 20 | 269128937219 |
| 21 | 1052049481859 |
| 22 | 4116715363799 |
| 23 | 16123801841549 |
| 24 | 63205303218875 |
| 25 | 247959266474051 |