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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 1 |
| 3 | 1 |
| 4 | 3 |
| 5 | 3 |
| 6 | 13 |
| 7 | 16 |
| 8 | 42 |
| 9 | 74 |
| 10 | 161 |
| 11 | 303 |
| 12 | 631 |
| 13 | 1212 |
| 14 | 2446 |
| 15 | 4847 |
| 16 | 9714 |
| 17 | 19142 |
| 18 | 38031 |
| 19 | 75367 |
| 20 | 149813 |
| 21 | 296961 |
| 22 | 589537 |
| 23 | 1169118 |
| 24 | 2319453 |
| 25 | 4603741 |
| 26 | 9137804 |
| 27 | 18132445 |
| 28 | 35982420 |
| 29 | 71413411 |
| 30 | 141734249 |
| 31 | 281295511 |
| 32 | 558288679 |
| 33 | 1107995542 |
| 34 | 2198965721 |
| 35 | 4364220336 |
[0,1,1,3,3,13,16,42,74,161,303,631,1212,2446,4847, 9714,19142,38031,75367,149813,296961,589537, 1169118,2319453,4603741,9137804,18132445,35982420, 71413411,141734249,281295511,558288679,1107995542, 2198965721,4364220336] |