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 | 4 |
| 2 | 17 |
| 3 | 76 |
| 4 | 353 |
| 5 | 1684 |
| 6 | 8177 |
| 7 | 40156 |
| 8 | 198593 |
| 9 | 986404 |
| 10 | 4912337 |
| 11 | 24502636 |
| 12 | 122336033 |
| 13 | 611148724 |
| 14 | 3054149297 |
| 15 | 15265963516 |
| 16 | 76315468673 |
| 17 | 381534296644 |
| 18 | 1907542343057 |
| 19 | 9537324294796 |
| 20 | 47685459212513 |
| 21 | 238423809278164 |
| 22 | 1192108586037617 |
| 23 | 5960511549128476 |