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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 1 |
| 6 | 1 |
| 7 | 1 |
| 8 | 2 |
| 9 | 3 |
| 10 | 4 |
| 11 | 5 |
| 12 | 9 |
| 13 | 18 |
| 14 | 34 |
| 15 | 93 |
| 16 | 180 |
| 17 | 348 |
| 18 | 724 |
| 19 | 3033 |
| 20 | 9666 |
| 21 | 24986 |
| 22 | 83761 |
| 23 | 261033 |
| 24 | 1023728 |
| 25 | 3923791 |
| 26 | 26128126 |
| 27 | 105734485 |
| 28 | 381740209 |
| 29 | 1895904805 |
| 30 | 14058722881 |
| 31 | 97964968321 |
| 32 | 517832518189 |
| 33 | 4364261070929 |
| 34 | 25225712161101 |
| 35 | 181840424632390 |
[1,1,1,1,1,1,1,1,2,3,4,5,9,18,34,93,180,348,724, 3033,9666,24986,83761,261033,1023728,3923791, 26128126,105734485,381740209,1895904805, 14058722881,97964968321,517832518189, 4364261070929,25225712161101,181840424632390] |