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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 3 |
| 5 | 6 |
| 6 | 9 |
| 7 | 16 |
| 8 | 25 |
| 9 | 43 |
| 10 | 66 |
| 11 | 108 |
| 12 | 166 |
| 13 | 269 |
| 14 | 408 |
| 15 | 643 |
| 16 | 975 |
| 17 | 1517 |
| 18 | 2277 |
| 19 | 3497 |
| 20 | 5223 |
| 21 | 7936 |
| 22 | 11803 |
| 23 | 17736 |
| 24 | 26219 |
| 25 | 39174 |
| 26 | 57594 |
| 27 | 85299 |
| 28 | 124957 |
| 29 | 183987 |
| 30 | 268158 |
| 31 | 392685 |
| 32 | 569987 |
| 33 | 830282 |
| 34 | 1200843 |
| 35 | 1740422 |
| 36 | 2507823 |
| 37 | 3620550 |
| 38 | 5197885 |
| 39 | 7472229 |
| 40 | 10694865 |
| 41 | 15319700 |
[1,1,2,3,6,9,16,25,43,66,108,166,269,408,643,975, 1517,2277,3497,5223,7936,11803,17736,26219,39174, 57594,85299,124957,183987,268158,392685,569987, 830282,1200843,1740422,2507823,3620550,5197885, 7472229,10694865,15319700] |