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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 0 |
| 2 | 1 |
| 3 | 3 |
| 4 | 9 |
| 5 | 24 |
| 6 | 60 |
| 7 | 145 |
| 8 | 342 |
| 9 | 791 |
| 10 | 1800 |
| 11 | 4041 |
| 12 | 8971 |
| 13 | 19733 |
| 14 | 43077 |
| 15 | 93441 |
| 16 | 201592 |
| 17 | 432867 |
| 18 | 925574 |
| 19 | 1971633 |
| 20 | 4185537 |
| 21 | 8857634 |
| 22 | 18691421 |
| 23 | 39339638 |
| 24 | 82599634 |
| 25 | 173050951 |
| 26 | 361825484 |
| 27 | 755140789 |
| 28 | 1573359111 |
| 29 | 3273103135 |
| 30 | 6799507189 |
| 31 | 14106802811 |
| 32 | 29231731788 |
[0,0,1,3,9,24,60,145,342,791,1800,4041,8971,19733, 43077,93441,201592,432867,925574,1971633,4185537, 8857634,18691421,39339638,82599634,173050951, 361825484,755140789,1573359111,3273103135, 6799507189,14106802811,29231731788] |