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 | 3 |
| 3 | 11 |
| 4 | 44 |
| 5 | 185 |
| 6 | 804 |
| 7 | 3579 |
| 8 | 16229 |
| 9 | 74690 |
| 10 | 347984 |
| 11 | 1638169 |
| 12 | 7780876 |
| 13 | 37245028 |
| 14 | 179503340 |
| 15 | 870374211 |
| 16 | 4243141332 |
| 17 | 20786340271 |
| 18 | 102275718924 |
| 19 | 505235129250 |
| 20 | 2504876652190 |
| 21 | 12459922302900 |
| 22 | 62167152967680 |
| 23 | 311040862133625 |