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 | 21 |
| 2 | 262 |
| 3 | 2525 |
| 4 | 20754 |
| 5 | 152946 |
| 6 | 1040556 |
| 7 | 6659037 |
| 8 | 40599130 |
| 9 | 237978598 |
| 10 | 1350216660 |
| 11 | 7453221490 |
| 12 | 40188242420 |
| 13 | 212349718980 |
| 14 | 1102352779992 |
| 15 | 5634083759325 |
| 16 | 28400234400810 |
| 17 | 141402315307550 |
| 18 | 696257439473860 |