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 | 3 |
| 3 | 7 |
| 4 | 17 |
| 5 | 37 |
| 6 | 99 |
| 7 | 243 |
| 8 | 633 |
| 9 | 1673 |
| 10 | 4425 |
| 11 | 11515 |
| 12 | 30471 |
| 13 | 80055 |
| 14 | 210157 |
| 15 | 553253 |
| 16 | 1454817 |
| 17 | 3821369 |
| 18 | 10040187 |
| 19 | 26360759 |
| 20 | 69201479 |
| 21 | 181628861 |
| 22 | 476576959 |
| 23 | 1250223373 |
| 24 | 3279352967 |
| 25 | 8600367843 |
| 26 | 22551873573 |
| 27 | 59128994931 |
| 28 | 155014246263 |
| 29 | 406350098913 |
| 30 | 1065104999651 |