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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 0 |
| 2 | 1 |
| 3 | 1 |
| 4 | 4 |
| 5 | 5 |
| 6 | 14 |
| 7 | 20 |
| 8 | 48 |
| 9 | 75 |
| 10 | 165 |
| 11 | 274 |
| 12 | 571 |
| 13 | 988 |
| 14 | 1988 |
| 15 | 3536 |
| 16 | 6953 |
| 17 | 12597 |
| 18 | 24396 |
| 19 | 44745 |
| 20 | 85786 |
| 21 | 158632 |
| 22 | 302104 |
| 23 | 561683 |
| 24 | 1064945 |
| 25 | 1987154 |
| 26 | 3756519 |
| 27 | 7026408 |
| 28 | 13256712 |
| 29 | 24835744 |
| 30 | 46796545 |
| 31 | 87763945 |
| 32 | 165225380 |
| 33 | 310088381 |
| 34 | 583440086 |
| 35 | 1095490524 |
[0,0,1,1,4,5,14,20,48,75,165,274,571,988,1988, 3536,6953,12597,24396,44745,85786,158632,302104, 561683,1064945,1987154,3756519,7026408,13256712, 24835744,46796545,87763945,165225380,310088381, 583440086,1095490524] |