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) |
|---|---|
| 1 | 7 |
| 2 | 9 |
| 3 | 77 |
| 4 | 79 |
| 5 | 97 |
| 6 | 99 |
| 7 | 777 |
| 8 | 779 |
| 9 | 797 |
| 10 | 799 |
| 11 | 977 |
| 12 | 979 |
| 13 | 997 |
| 14 | 999 |
| 15 | 7777 |
| 16 | 7779 |
| 17 | 7797 |
| 18 | 7799 |
| 19 | 7977 |
| 20 | 7979 |
| 21 | 7997 |
| 22 | 7999 |
| 23 | 9777 |
| 24 | 9779 |
| 25 | 9797 |
| 26 | 9799 |
| 27 | 9977 |
| 28 | 9979 |
| 29 | 9997 |
| 30 | 9999 |
| 31 | 77777 |
| 32 | 77779 |
| 33 | 77797 |
| 34 | 77799 |
| 35 | 77977 |
| 36 | 77979 |
| 37 | 77997 |
| 38 | 77999 |
| 39 | 79777 |
| 40 | 79779 |
| 41 | 79797 |
| 42 | 79799 |
| 43 | 79977 |
| 44 | 79979 |