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) |
|---|---|
| 2 | 2 |
| 3 | 23 |
| 4 | 292 |
| 5 | 4068 |
| 6 | 62861 |
| 7 | 1075562 |
| 8 | 20275944 |
| 9 | 418724047 |
| 10 | 9418874022 |
| 11 | 229535650138 |
| 12 | 6029910590473 |
| 13 | 169978358728536 |
| 14 | 5120224516689050 |
| 15 | 164192864744507615 |
| 16 | 5585978669387706724 |
| 17 | 200988595873323113508 |
| 18 | 7626780547253339197109 |
| 19 | 304431018444668653351250 |
| 20 | 12752396616363975496913952 |
| 21 | 559388848572350998030227895 |