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) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 6 |
| 4 | 17 |
| 5 | 50 |
| 6 | 143 |
| 7 | 416 |
| 8 | 1199 |
| 9 | 3474 |
| 10 | 10049 |
| 11 | 29119 |
| 12 | 84377 |
| 13 | 244748 |
| 14 | 710199 |
| 15 | 2062274 |
| 16 | 5991418 |
| 17 | 17416401 |
| 18 | 50652248 |
| 19 | 147384676 |
| 20 | 429043390 |
| 21 | 1249508947 |
| 22 | 3640449679 |
| 23 | 10610613552 |
| 24 | 30937605076 |
| 25 | 90237313083 |
| 26 | 263288153074 |
| 27 | 768449666117 |
| 28 | 2243530461067 |
| 29 | 6552016136667 |