n | a(n) |
---|---|
0 | 1 |
1 | 7 |
2 | 21 |
3 | 56 |
4 | 147 |
5 | 385 |
6 | 1008 |
7 | 2639 |
8 | 6909 |
9 | 18088 |
10 | 47355 |
11 | 123977 |
12 | 324576 |
13 | 849751 |
14 | 2224677 |
15 | 5824280 |
16 | 15248163 |
17 | 39920209 |
18 | 104512464 |
19 | 273617183 |
20 | 716339085 |
21 | 1875400072 |
22 | 4909861131 |
23 | 12854183321 |
[1,7,21,56,147,385,1008,2639,6909,18088,47355, 123977,324576,849751,2224677,5824280,15248163, 39920209,104512464,273617183,716339085,1875400072, 4909861131,12854183321] |