n | a(n) |
---|---|
0 | 0 |
1 | 1 |
2 | 4 |
3 | 7 |
4 | 20 |
5 | 45 |
6 | 112 |
7 | 267 |
8 | 648 |
9 | 1561 |
10 | 3772 |
11 | 9103 |
12 | 21980 |
13 | 53061 |
14 | 128104 |
15 | 309267 |
16 | 746640 |
17 | 1802545 |
18 | 4351732 |
19 | 10506007 |
20 | 25363748 |
21 | 61233501 |
22 | 147830752 |
23 | 356895003 |
24 | 861620760 |
25 | 2080136521 |
26 | 5021893804 |
27 | 12123924127 |
28 | 29269742060 |
29 | 70663408245 |
[0,1,4,7,20,45,112,267,648,1561,3772,9103,21980, 53061,128104,309267,746640,1802545,4351732, 10506007,25363748,61233501,147830752,356895003, 861620760,2080136521,5021893804,12123924127, 29269742060,70663408245] |