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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 1 |
| 6 | 4 |
| 7 | 13 |
| 8 | 32 |
| 9 | 74 |
| 10 | 155 |
| 11 | 316 |
| 12 | 612 |
| 13 | 1160 |
| 14 | 2126 |
| 15 | 3829 |
| 16 | 6737 |
| 17 | 11672 |
| 18 | 19856 |
| 19 | 33332 |
| 20 | 55112 |
| 21 | 90014 |
| 22 | 145105 |
| 23 | 231200 |
| 24 | 363985 |
| 25 | 566692 |
| 26 | 872274 |
| 27 | 1328167 |
| 28 | 2000224 |
| 29 | 2980316 |
| 30 | 4393106 |
| 31 | 6407555 |
| 32 | 9246741 |
| 33 | 13204470 |
| 34 | 18657868 |
| 35 | 26088224 |
| 36 | 36095090 |
[0,0,0,0,0,1,4,13,32,74,155,316,612,1160,2126, 3829,6737,11672,19856,33332,55112,90014,145105, 231200,363985,566692,872274,1328167,2000224, 2980316,4393106,6407555,9246741,13204470,18657868, 26088224,36095090] |