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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 1 |
| 3 | 1 |
| 4 | 3 |
| 5 | 5 |
| 6 | 15 |
| 7 | 28 |
| 8 | 87 |
| 9 | 176 |
| 10 | 550 |
| 11 | 1179 |
| 12 | 3688 |
| 13 | 8269 |
| 14 | 25804 |
| 15 | 59832 |
| 16 | 186190 |
| 17 | 443407 |
| 18 | 1375388 |
| 19 | 3346702 |
| 20 | 10348509 |
| 21 | 25632265 |
| 22 | 79020511 |
| 23 | 198670299 |
| 24 | 610740694 |
| 25 | 1555187172 |
| 26 | 4768244803 |
| 27 | 12276230777 |
| 28 | 37546795678 |
| 29 | 97601239282 |
| 30 | 297831479850 |
| 31 | 780790439063 |
| 32 | 2377538260547 |
[0,1,1,3,5,15,28,87,176,550,1179,3688,8269,25804, 59832,186190,443407,1375388,3346702,10348509, 25632265,79020511,198670299,610740694,1555187172, 4768244803,12276230777,37546795678,97601239282, 297831479850,780790439063,2377538260547] |