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 | 0 |
| 1 | 1 |
| 2 | 55 |
| 3 | 1015 |
| 4 | 9455 |
| 5 | 56980 |
| 6 | 255346 |
| 7 | 924490 |
| 8 | 2850730 |
| 9 | 7757035 |
| 10 | 19096385 |
| 11 | 43312841 |
| 12 | 91753025 |
| 13 | 183453270 |
| 14 | 349074740 |
| 15 | 636310340 |
| 16 | 1117143236 |
| 17 | 1897397285 |
| 18 | 3129084635 |
| 19 | 5026125195 |
| 20 | 7884086595 |
| 21 | 12104671656 |
| 22 | 18225763270 |
| 23 | 26957923950 |
| 24 | 39228339150 |
| 25 | 56233289775 |
| 26 | 79500340101 |
| 27 | 110961532605 |