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 | 3 |
| 2 | 7 |
| 3 | 15 |
| 4 | 39 |
| 5 | 87 |
| 6 | 200 |
| 7 | 438 |
| 8 | 981 |
| 9 | 2135 |
| 10 | 4639 |
| 11 | 9971 |
| 12 | 21424 |
| 13 | 45699 |
| 14 | 97096 |
| 15 | 205563 |
| 16 | 433895 |
| 17 | 913244 |
| 18 | 1917491 |
| 19 | 4016704 |
| 20 | 8397235 |
| 21 | 17521118 |
| 22 | 36497171 |
| 23 | 75900377 |
| 24 | 157619705 |
| 25 | 326868209 |
| 26 | 676998896 |
| 27 | 1400510860 |
| 28 | 2894068715 |
| 29 | 5974185368 |
| 30 | 12320552102 |
| 31 | 25385332979 |