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 | 1 |
| 2 | 2 |
| 3 | 6 |
| 4 | 21 |
| 5 | 79 |
| 6 | 312 |
| 7 | 1277 |
| 8 | 5369 |
| 9 | 23049 |
| 10 | 100612 |
| 11 | 445214 |
| 12 | 1992606 |
| 13 | 9004260 |
| 14 | 41025315 |
| 15 | 188259072 |
| 16 | 869305315 |
| 17 | 4036286518 |
| 18 | 18832973733 |
| 19 | 88259024068 |
| 20 | 415252542641 |
| 21 | 1960718710035 |
| 22 | 9288106921038 |
| 23 | 44129146527731 |