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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 2 |
| 6 | 2 |
| 7 | 4 |
| 8 | 5 |
| 9 | 8 |
| 10 | 11 |
| 11 | 18 |
| 12 | 25 |
| 13 | 40 |
| 14 | 58 |
| 15 | 90 |
| 16 | 135 |
| 17 | 210 |
| 18 | 316 |
| 19 | 492 |
| 20 | 750 |
| 21 | 1164 |
| 22 | 1791 |
| 23 | 2786 |
| 24 | 4305 |
| 25 | 6710 |
| 26 | 10420 |
| 27 | 16264 |
| 28 | 25350 |
| 29 | 39650 |
| 30 | 61967 |
| 31 | 97108 |
| 32 | 152145 |
| 33 | 238818 |
| 34 | 374955 |
| 35 | 589520 |
| 36 | 927200 |
| 37 | 1459960 |
| 38 | 2299854 |
| 39 | 3626200 |
| 40 | 5720274 |
| 41 | 9030450 |
| 42 | 14263078 |
[1,1,1,1,2,2,4,5,8,11,18,25,40,58,90,135,210,316, 492,750,1164,1791,2786,4305,6710,10420,16264, 25350,39650,61967,97108,152145,238818,374955, 589520,927200,1459960,2299854,3626200,5720274, 9030450,14263078] |