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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 1 |
| 3 | 2 |
| 4 | 2 |
| 5 | 4 |
| 6 | 8 |
| 7 | 13 |
| 8 | 25 |
| 9 | 49 |
| 10 | 91 |
| 11 | 177 |
| 12 | 349 |
| 13 | 681 |
| 14 | 1349 |
| 15 | 2693 |
| 16 | 5377 |
| 17 | 10806 |
| 18 | 21820 |
| 19 | 44163 |
| 20 | 89721 |
| 21 | 182868 |
| 22 | 373616 |
| 23 | 765341 |
| 24 | 1571551 |
| 25 | 3233690 |
| 26 | 6667242 |
| 27 | 13772469 |
| 28 | 28498419 |
| 29 | 59065838 |
| 30 | 122606998 |
| 31 | 254865837 |
| 32 | 530507839 |
| 33 | 1105663034 |
| 34 | 2307131590 |
| 35 | 4819623077 |
| 36 | 10079039819 |
| 37 | 21099213611 |
| 38 | 44211213545 |
[1,0,1,2,2,4,8,13,25,49,91,177,349,681,1349,2693, 5377,10806,21820,44163,89721,182868,373616,765341, 1571551,3233690,6667242,13772469,28498419, 59065838,122606998,254865837,530507839,1105663034, 2307131590,4819623077,10079039819,21099213611, 44211213545] |