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 | 16 |
| 3 | 114 |
| 4 | 1013 |
| 5 | 10973 |
| 6 | 142980 |
| 7 | 2208958 |
| 8 | 39796747 |
| 9 | 822252765 |
| 10 | 19192927840 |
| 11 | 499725372072 |
| 12 | 14361189358332 |
| 13 | 451551559895244 |
| 14 | 15419952421504604 |
| 15 | 568327808746891014 |
| 16 | 22486286328779957223 |
| 17 | 950624702855155671101 |
| 18 | 42765431507866487733504 |
| 19 | 2039838152324158031743570 |