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 | 10 |
| 4 | 59 |
| 5 | 446 |
| 6 | 3965 |
| 7 | 41098 |
| 8 | 484090 |
| 9 | 6390488 |
| 10 | 93419519 |
| 11 | 1498268466 |
| 12 | 26159936547 |
| 13 | 494036061550 |
| 14 | 10035451706821 |
| 15 | 218207845446062 |
| 16 | 5057251219268460 |
| 17 | 124462048466812950 |
| 18 | 3241773988588098756 |
| 19 | 89093816361187396674 |
| 20 | 2576652694087142999421 |