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) |
|---|---|
| 2 | 20 |
| 3 | 651 |
| 4 | 8344 |
| 5 | 64667 |
| 6 | 361884 |
| 7 | 1607125 |
| 8 | 5997992 |
| 9 | 19535997 |
| 10 | 57014776 |
| 11 | 151986562 |
| 12 | 375470160 |
| 13 | 869285378 |
| 14 | 1902886024 |
| 15 | 3966657702 |
| 16 | 7920130544 |
| 17 | 15220758070 |
| 18 | 28268206764 |
| 19 | 50910912965 |
| 20 | 89176474920 |
| 21 | 152305796565 |
| 22 | 254193384900 |
| 23 | 415363487955 |
| 24 | 665644575960 |
| 25 | 1047743815755 |