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 | 3 |
| 4 | 9 |
| 5 | 37 |
| 6 | 190 |
| 7 | 1181 |
| 8 | 8564 |
| 9 | 70914 |
| 10 | 659810 |
| 11 | 6811371 |
| 12 | 77232836 |
| 13 | 953969548 |
| 14 | 12747856402 |
| 15 | 183218649413 |
| 16 | 2818050980941 |
| 17 | 46182485773217 |
| 18 | 803323102085452 |
| 19 | 14781372445602234 |
| 20 | 286838921699435184 |
| 21 | 5854404018902152208 |
| 22 | 125367868007259046305 |
| 23 | 2810511319383912299122 |