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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 3 |
| 4 | 13 |
| 5 | 20 |
| 6 | 41 |
| 7 | 76 |
| 8 | 176 |
| 9 | 325 |
| 10 | 638 |
| 11 | 1353 |
| 12 | 2533 |
| 13 | 5223 |
| 14 | 10186 |
| 15 | 20504 |
| 16 | 40775 |
| 17 | 80661 |
| 18 | 163765 |
| 19 | 318602 |
| 20 | 649948 |
| 21 | 1268922 |
| 22 | 2571531 |
| 23 | 5082895 |
| 24 | 10217300 |
| 25 | 20327307 |
| 26 | 40399966 |
| 27 | 82164918 |
| 28 | 160343669 |
| 29 | 324931245 |
| 30 | 640501167 |
| 31 | 1290990369 |
| 32 | 2567150515 |
[1,3,3,13,20,41,76,176,325,638,1353,2533,5223, 10186,20504,40775,80661,163765,318602,649948, 1268922,2571531,5082895,10217300,20327307, 40399966,82164918,160343669,324931245,640501167, 1290990369,2567150515] |