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 | 9 |
| 3 | 116 |
| 4 | 670 |
| 5 | 2580 |
| 6 | 7735 |
| 7 | 19544 |
| 8 | 43596 |
| 9 | 88440 |
| 10 | 166485 |
| 11 | 295020 |
| 12 | 497354 |
| 13 | 804076 |
| 14 | 1254435 |
| 15 | 1897840 |
| 16 | 2795480 |
| 17 | 4022064 |
| 18 | 5667681 |
| 19 | 7839780 |
| 20 | 10665270 |
| 21 | 14292740 |
| 22 | 18894799 |
| 23 | 24670536 |
| 24 | 31848100 |
| 25 | 40687400 |
| 26 | 51482925 |
| 27 | 64566684 |
| 28 | 80311266 |
| 29 | 99133020 |
| 30 | 121495355 |
| 31 | 147912160 |