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 | 12 |
| 2 | 123 |
| 3 | 1334 |
| 4 | 14645 |
| 5 | 161056 |
| 6 | 1771567 |
| 7 | 19487178 |
| 8 | 214358889 |
| 9 | 2357947700 |
| 10 | 25937424611 |
| 11 | 285311670622 |
| 12 | 3138428376733 |
| 13 | 34522712143944 |
| 14 | 379749833583255 |
| 15 | 4177248169415666 |
| 16 | 45949729863572177 |
| 17 | 505447028499293788 |
| 18 | 5559917313492231499 |
| 19 | 61159090448414546310 |
| 20 | 672749994932560009221 |