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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 6 |
| 3 | 18 |
| 4 | 42 |
| 5 | 90 |
| 6 | 186 |
| 7 | 378 |
| 8 | 762 |
| 9 | 1530 |
| 10 | 3066 |
| 11 | 6138 |
| 12 | 12282 |
| 13 | 24570 |
| 14 | 49146 |
| 15 | 98298 |
| 16 | 196602 |
| 17 | 393210 |
| 18 | 786426 |
| 19 | 1572858 |
| 20 | 3145722 |
| 21 | 6291450 |
| 22 | 12582906 |
| 23 | 25165818 |
| 24 | 50331642 |
| 25 | 100663290 |
| 26 | 201326586 |
| 27 | 402653178 |
| 28 | 805306362 |
| 29 | 1610612730 |
| 30 | 3221225466 |
| 31 | 6442450938 |
| 32 | 12884901882 |
[1,6,18,42,90,186,378,762,1530,3066,6138,12282, 24570,49146,98298,196602,393210,786426,1572858, 3145722,6291450,12582906,25165818,50331642, 100663290,201326586,402653178,805306362, 1610612730,3221225466,6442450938,12884901882] |