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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 5 |
| 3 | 12 |
| 4 | 29 |
| 5 | 1752 |
| 6 | 3533 |
| 7 | 8818 |
| 8 | 21169 |
| 9 | 51156 |
| 10 | 3090529 |
| 11 | 6232214 |
| 12 | 15554957 |
| 13 | 37342128 |
| 14 | 90239213 |
| 15 | 5451694908 |
| 16 | 10993629029 |
| 17 | 27438952966 |
| 18 | 65871534961 |
| 19 | 159182022888 |
| 20 | 9616792908241 |
| 21 | 19392767839370 |
| 22 | 48402328586981 |
| 23 | 116197425013332 |
| 24 | 280797178613645 |
[1,2,5,12,29,1752,3533,8818,21169,51156,3090529, 6232214,15554957,37342128,90239213,5451694908, 10993629029,27438952966,65871534961,159182022888, 9616792908241,19392767839370,48402328586981, 116197425013332,280797178613645] |