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 | 3 |
| 2 | 55 |
| 3 | 300 |
| 4 | 3003 |
| 5 | 5050 |
| 6 | 500500 |
| 7 | 50005000 |
| 8 | 5000050000 |
| 9 | 33050333550 |
| 10 | 500000500000 |
| 11 | 3505500530535 |
| 12 | 50000005000000 |
| 13 | 53555035005300 |
| 14 | 355300503533550 |
| 15 | 5000000050000000 |
| 16 | 50035505550330300 |
| 17 | 300555503500333305 |
| 18 | 500000000500000000 |
| 19 | 50000000005000000000 |