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 | 7 |
| 3 | 38 |
| 4 | 189 |
| 5 | 904 |
| 6 | 4242 |
| 7 | 19723 |
| 8 | 91366 |
| 9 | 423124 |
| 10 | 1963169 |
| 11 | 9138416 |
| 12 | 42718416 |
| 13 | 200656644 |
| 14 | 947423923 |
| 15 | 4497458118 |
| 16 | 21465533955 |
| 17 | 103001236168 |
| 18 | 496832195860 |
| 19 | 2408570061810 |
| 20 | 11732479621260 |
| 21 | 57410235742920 |
| 22 | 282124153996425 |
| 23 | 1391949415580256 |
| 24 | 6893204658852960 |
| 25 | 34254642268407820 |
| 26 | 170769192927927532 |
| 27 | 853864581906454264 |
| 28 | 4281167768111675732 |
| 29 | 21519922572920909984 |