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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 6 |
| 4 | 8 |
| 5 | 30 |
| 6 | 36 |
| 7 | 126 |
| 8 | 160 |
| 9 | 450 |
| 10 | 740 |
| 11 | 2046 |
| 12 | 2592 |
| 13 | 8190 |
| 14 | 12824 |
| 15 | 30030 |
| 16 | 48640 |
| 17 | 131070 |
| 18 | 194508 |
| 19 | 524286 |
| 20 | 812840 |
| 21 | 1987818 |
| 22 | 3486824 |
| 23 | 8388606 |
| 24 | 12400368 |
| 25 | 33348150 |
| 26 | 56700072 |
| 27 | 128800098 |
| 28 | 219681672 |
| 29 | 536870910 |
| 30 | 861181320 |
| 31 | 2147483646 |
| 32 | 3555730432 |
[1,2,6,8,30,36,126,160,450,740,2046,2592,8190, 12824,30030,48640,131070,194508,524286,812840, 1987818,3486824,8388606,12400368,33348150, 56700072,128800098,219681672,536870910,861181320, 2147483646,3555730432] |