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 | 1 |
| 3 | 5 |
| 4 | 34 |
| 5 | 288 |
| 6 | 3102 |
| 7 | 39242 |
| 8 | 573654 |
| 9 | 9484003 |
| 10 | 175036065 |
| 11 | 3568736050 |
| 12 | 79697415569 |
| 13 | 1935425955944 |
| 14 | 50794210191337 |
| 15 | 1432898704970561 |
| 16 | 43244525933606928 |
| 17 | 1390448844972918928 |
| 18 | 47455314531812444788 |
| 19 | 1713525997666221196906 |
| 20 | 65266335503957271588042 |
| 21 | 2615307907226341637828915 |