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 | 5 |
| 3 | 36 |
| 4 | 325 |
| 5 | 3468 |
| 6 | 42519 |
| 7 | 590268 |
| 8 | 9201740 |
| 9 | 160150252 |
| 10 | 3095440553 |
| 11 | 66068011710 |
| 12 | 1547572760559 |
| 13 | 39529002357409 |
| 14 | 1094096683131616 |
| 15 | 32622859912512090 |
| 16 | 1042350065213470532 |
| 17 | 35521574976088978133 |
| 18 | 1285782300453328211074 |
| 19 | 49256935742079848796102 |