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 | 2 |
| 3 | 19 |
| 4 | 498 |
| 5 | 2114 |
| 6 | 8351 |
| 7 | 8381 |
| 8 | 59704 |
| 9 | 233890 |
| 10 | 291963 |
| 11 | 1119181 |
| 12 | 1507131 |
| 13 | 1839746 |
| 14 | 9768399 |
| 15 | 40844982 |
| 16 | 94852115 |
| 17 | 138032741 |
| 18 | 443653568 |
| 19 | 453853664 |
| 20 | 2491818901 |