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 | 4 |
| 3 | 14 |
| 4 | 51 |
| 5 | 187 |
| 6 | 695 |
| 7 | 2606 |
| 8 | 9842 |
| 9 | 37386 |
| 10 | 142693 |
| 11 | 546790 |
| 12 | 2102312 |
| 13 | 8106308 |
| 14 | 31335060 |
| 15 | 121390028 |
| 16 | 471159761 |
| 17 | 1831860961 |
| 18 | 7133082300 |
| 19 | 27813493104 |
| 20 | 108585087657 |
| 21 | 424396534100 |
| 22 | 1660418620528 |
| 23 | 6502345229958 |
| 24 | 25485677806201 |
| 25 | 99969379431223 |
| 26 | 392424954930562 |
| 27 | 1541494622610616 |
| 28 | 6059022365002926 |
| 29 | 23829761312067896 |