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 | 10 |
| 2 | 75 |
| 3 | 440 |
| 4 | 2255 |
| 5 | 10362 |
| 6 | 43945 |
| 7 | 174460 |
| 8 | 656370 |
| 9 | 2359500 |
| 10 | 8158722 |
| 11 | 27275040 |
| 12 | 88524930 |
| 13 | 279892380 |
| 14 | 864508590 |
| 15 | 2614740216 |
| 16 | 7759693095 |
| 17 | 22634343270 |
| 18 | 64990287285 |
| 19 | 183929970840 |
| 20 | 513661549401 |
| 21 | 1416970676550 |