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 | 0 |
| 2 | 7 |
| 3 | 19 |
| 4 | 98 |
| 5 | 387 |
| 6 | 1685 |
| 7 | 7064 |
| 8 | 30043 |
| 9 | 127071 |
| 10 | 538594 |
| 11 | 2281015 |
| 12 | 9663353 |
| 13 | 40933296 |
| 14 | 173398367 |
| 15 | 734523803 |
| 16 | 3111498370 |
| 17 | 13180509531 |
| 18 | 55833549037 |
| 19 | 236514685384 |
| 20 | 1001892323411 |
| 21 | 4244083925895 |
| 22 | 17978228112962 |
| 23 | 76156996238639 |
| 24 | 322606213292593 |
| 25 | 1366581849044832 |