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| n | a(n) |
|---|---|
| 1 | 3 |
| 2 | 3 |
| 3 | 2 |
| 4 | 7 |
| 5 | 9 |
| 6 | 6 |
| 7 | 22 |
| 8 | 30 |
| 9 | 20 |
| 10 | 75 |
| 11 | 105 |
| 12 | 70 |
| 13 | 266 |
| 14 | 378 |
| 15 | 252 |
| 16 | 966 |
| 17 | 1386 |
| 18 | 924 |
| 19 | 3564 |
| 20 | 5148 |
| 21 | 3432 |
| 22 | 13299 |
| 23 | 19305 |
| 24 | 12870 |
| 25 | 50050 |
| 26 | 72930 |
| 27 | 48620 |
| 28 | 189618 |
| 29 | 277134 |
| 30 | 184756 |
| 31 | 722228 |
| 32 | 1058148 |
| 33 | 705432 |
| 34 | 2762942 |
| 35 | 4056234 |
| 36 | 2704156 |
| 37 | 10608612 |
| 38 | 15600900 |
| 39 | 10400600 |
| 40 | 40859500 |
[3,3,2,7,9,6,22,30,20,75,105,70,266,378,252,966, 1386,924,3564,5148,3432,13299,19305,12870,50050, 72930,48620,189618,277134,184756,722228,1058148, 705432,2762942,4056234,2704156,10608612,15600900, 10400600,40859500] |