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 | 10 |
| 4 | 29 |
| 5 | 88 |
| 6 | 264 |
| 7 | 790 |
| 8 | 2366 |
| 9 | 7086 |
| 10 | 21216 |
| 11 | 63523 |
| 12 | 190201 |
| 13 | 569485 |
| 14 | 1705121 |
| 15 | 5105383 |
| 16 | 15286247 |
| 17 | 45769238 |
| 18 | 137039743 |
| 19 | 410316854 |
| 20 | 1228548190 |
| 21 | 3678451550 |
| 22 | 11013817655 |
| 23 | 32976968175 |
| 24 | 98737827756 |
| 25 | 295635383297 |
| 26 | 885175234817 |
| 27 | 2650343093602 |
| 28 | 7935511791620 |
| 29 | 23760073760720 |
| 30 | 71141108467679 |