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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 4 |
| 3 | 6 |
| 4 | 9 |
| 5 | 14 |
| 6 | 20 |
| 7 | 28 |
| 8 | 40 |
| 9 | 54 |
| 10 | 72 |
| 11 | 98 |
| 12 | 129 |
| 13 | 168 |
| 14 | 220 |
| 15 | 282 |
| 16 | 360 |
| 17 | 460 |
| 18 | 580 |
| 19 | 728 |
| 20 | 912 |
| 21 | 1134 |
| 22 | 1404 |
| 23 | 1734 |
| 24 | 2129 |
| 25 | 2604 |
| 26 | 3180 |
| 27 | 3864 |
| 28 | 4680 |
| 29 | 5658 |
| 30 | 6812 |
| 31 | 8182 |
| 32 | 9808 |
| 33 | 11718 |
| 34 | 13968 |
| 35 | 16618 |
| 36 | 19720 |
| 37 | 23350 |
| 38 | 27600 |
| 39 | 32550 |
| 40 | 38313 |
[1,2,4,6,9,14,20,28,40,54,72,98,129,168,220,282, 360,460,580,728,912,1134,1404,1734,2129,2604,3180, 3864,4680,5658,6812,8182,9808,11718,13968,16618, 19720,23350,27600,32550,38313] |