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 | 2 |
| 2 | 61 |
| 3 | 124 |
| 4 | 3781 |
| 5 | 7686 |
| 6 | 234361 |
| 7 | 476408 |
| 8 | 14526601 |
| 9 | 29529610 |
| 10 | 900414901 |
| 11 | 1830359412 |
| 12 | 55811197261 |
| 13 | 113452753934 |
| 14 | 3459393815281 |
| 15 | 7032240384496 |
| 16 | 214426605350161 |
| 17 | 435885451084818 |
| 18 | 13290990137894701 |
| 19 | 27017865726874220 |
| 20 | 823826961944121301 |
| 21 | 1674671789615116822 |