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 | 2 |
| 2 | 2 |
| 3 | 5 |
| 4 | 15 |
| 5 | 52 |
| 6 | 193 |
| 7 | 765 |
| 8 | 3143 |
| 9 | 13323 |
| 10 | 57670 |
| 11 | 254040 |
| 12 | 1134249 |
| 13 | 5122124 |
| 14 | 23349966 |
| 15 | 107310784 |
| 16 | 496633774 |
| 17 | 2312539465 |
| 18 | 10826481544 |
| 19 | 50929829953 |
| 20 | 240616214596 |
| 21 | 1141195080020 |
| 22 | 5431477088428 |
| 23 | 25933525825389 |
| 24 | 124185539096075 |
| 25 | 596268057962349 |
| 26 | 2869992942831031 |
| 27 | 13845453533124431 |
| 28 | 66934180769445444 |
| 29 | 324218809545624984 |