n | a(n) |
---|---|
0 | 0 |
1 | 1 |
2 | 4 |
3 | 14 |
4 | 46 |
5 | 147 |
6 | 462 |
7 | 1437 |
8 | 4438 |
9 | 13637 |
10 | 41746 |
11 | 127426 |
12 | 388076 |
13 | 1179739 |
14 | 3581052 |
15 | 10856790 |
16 | 32880942 |
17 | 99496293 |
18 | 300845658 |
19 | 909073356 |
20 | 2745419352 |
21 | 8287110075 |
22 | 25003877784 |
23 | 75412396575 |
24 | 227366950140 |
25 | 685293578217 |
26 | 2064924137152 |
27 | 6220442229932 |
28 | 18734334462598 |
[0,1,4,14,46,147,462,1437,4438,13637,41746,127426, 388076,1179739,3581052,10856790,32880942,99496293, 300845658,909073356,2745419352,8287110075, 25003877784,75412396575,227366950140,685293578217, 2064924137152,6220442229932,18734334462598] |