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 | 3 |
| 2 | 9 |
| 3 | 37 |
| 4 | 210 |
| 5 | 1575 |
| 6 | 14943 |
| 7 | 173109 |
| 8 | 2381814 |
| 9 | 38087355 |
| 10 | 695745075 |
| 11 | 14317460370 |
| 12 | 328142173159 |
| 13 | 8296618775100 |
| 14 | 229557238129530 |
| 15 | 6903176055689085 |
| 16 | 224285333475911340 |
| 17 | 7832574292981396104 |
| 18 | 292678312428437482293 |