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 | 5 |
| 1 | 29 |
| 2 | 149 |
| 3 | 749 |
| 4 | 3749 |
| 5 | 18749 |
| 6 | 93749 |
| 7 | 468749 |
| 8 | 2343749 |
| 9 | 11718749 |
| 10 | 58593749 |
| 11 | 292968749 |
| 12 | 1464843749 |
| 13 | 7324218749 |
| 14 | 36621093749 |
| 15 | 183105468749 |
| 16 | 915527343749 |
| 17 | 4577636718749 |
| 18 | 22888183593749 |
| 19 | 114440917968749 |
| 20 | 572204589843749 |
| 21 | 2861022949218749 |