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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 1 |
| 3 | 1 |
| 4 | 2 |
| 5 | 3 |
| 6 | 7 |
| 7 | 14 |
| 8 | 35 |
| 9 | 81 |
| 10 | 216 |
| 11 | 557 |
| 12 | 1583 |
| 13 | 4444 |
| 14 | 13389 |
| 15 | 40313 |
| 16 | 128110 |
| 17 | 409519 |
| 18 | 1366479 |
| 19 | 4603338 |
| 20 | 16064047 |
| 21 | 56708713 |
| 22 | 206238116 |
| 23 | 759535545 |
| 24 | 2870002519 |
| 25 | 10986716984 |
| 26 | 43019064953 |
| 27 | 170663829777 |
| 28 | 690840124506 |
| 29 | 2832976091771 |
| 30 | 11831091960887 |
| 31 | 50040503185030 |
[1,0,1,1,2,3,7,14,35,81,216,557,1583,4444,13389, 40313,128110,409519,1366479,4603338,16064047, 56708713,206238116,759535545,2870002519, 10986716984,43019064953,170663829777,690840124506, 2832976091771,11831091960887,50040503185030] |