n | a(n) |
---|---|
0 | 1 |
1 | 4 |
2 | 28 |
3 | 220 |
4 | 1819 |
5 | 15484 |
6 | 134320 |
7 | 1180764 |
8 | 10482340 |
9 | 93766288 |
10 | 843822148 |
11 | 7631018564 |
12 | 69291185474 |
13 | 631334484200 |
14 | 5769124912320 |
15 | 52851389067420 |
16 | 485242722376524 |
17 | 4463782855666480 |
18 | 41133265444555120 |
[1,4,28,220,1819,15484,134320,1180764,10482340, 93766288,843822148,7631018564,69291185474, 631334484200,5769124912320,52851389067420, 485242722376524,4463782855666480, 41133265444555120] |