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 | 0 |
| 2 | 32 |
| 3 | 332 |
| 4 | 2908 |
| 5 | 23900 |
| 6 | 192844 |
| 7 | 1547068 |
| 8 | 12388068 |
| 9 | 99135316 |
| 10 | 793162780 |
| 11 | 6345516140 |
| 12 | 50764701756 |
| 13 | 406119132924 |
| 14 | 3248957101772 |
| 15 | 25991667561644 |
| 16 | 207933369171996 |
| 17 | 1663467029827132 |
| 18 | 13307736442512524 |
| 19 | 106461892083564380 |
| 20 | 851695138117736668 |
| 21 | 6813561108806027412 |