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 | 3 |
| 2 | 14 |
| 3 | 79 |
| 4 | 521 |
| 5 | 3876 |
| 6 | 31935 |
| 7 | 287225 |
| 8 | 2791122 |
| 9 | 29066589 |
| 10 | 322292257 |
| 11 | 3784650052 |
| 12 | 46857941291 |
| 13 | 609360372095 |
| 14 | 8296220760974 |
| 15 | 117914344818807 |
| 16 | 1745211622467633 |
| 17 | 26838798853062516 |
| 18 | 428009369349905497 |
| 19 | 7065576909286562195 |
| 20 | 120545067517808693300 |
| 21 | 2122393931891338237325 |
| 22 | 38512344746420591905771 |