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 | 2 |
| 4 | 5 |
| 5 | 10 |
| 6 | 28 |
| 7 | 71 |
| 8 | 194 |
| 9 | 532 |
| 10 | 1495 |
| 11 | 4256 |
| 12 | 12176 |
| 13 | 35251 |
| 14 | 102664 |
| 15 | 300260 |
| 16 | 881909 |
| 17 | 2599948 |
| 18 | 7688164 |
| 19 | 22788527 |
| 20 | 67676144 |
| 21 | 201308938 |
| 22 | 599676445 |
| 23 | 1788564038 |
| 24 | 5339905904 |
| 25 | 15956230705 |
| 26 | 47713265536 |
| 27 | 142763240666 |
| 28 | 427390085963 |
| 29 | 1280058256294 |
| 30 | 3835332884686 |