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 | 0 |
| 1 | 1 |
| 2 | 2 |
| 3 | 5 |
| 4 | 13 |
| 5 | 35 |
| 6 | 95 |
| 7 | 262 |
| 8 | 727 |
| 9 | 2033 |
| 10 | 5714 |
| 11 | 16136 |
| 12 | 45733 |
| 13 | 130046 |
| 14 | 370803 |
| 15 | 1059838 |
| 16 | 3035591 |
| 17 | 8710736 |
| 18 | 25036934 |
| 19 | 72069134 |
| 20 | 207727501 |
| 21 | 599461094 |
| 22 | 1731818878 |
| 23 | 5008149658 |
| 24 | 14496034714 |
| 25 | 41993925955 |
| 26 | 121747732406 |
| 27 | 353221737526 |
| 28 | 1025471857282 |
| 29 | 2978995353959 |
| 30 | 8658997820084 |