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 | 0 |
| 2 | 1 |
| 3 | 5 |
| 4 | 11 |
| 5 | 59 |
| 6 | 179 |
| 7 | 1259 |
| 8 | 2519 |
| 9 | 7559 |
| 10 | 37799 |
| 11 | 415799 |
| 12 | 1247399 |
| 13 | 16216199 |
| 14 | 113513399 |
| 15 | 567566999 |
| 16 | 1135133999 |
| 17 | 19297277999 |
| 18 | 57891833999 |
| 19 | 1099944845999 |
| 20 | 5499724229999 |
| 21 | 38498069609999 |
| 22 | 423478765709999 |
| 23 | 9740011611329999 |