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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 6 |
| 4 | 13 |
| 5 | 28 |
| 6 | 56 |
| 7 | 115 |
| 8 | 237 |
| 9 | 474 |
| 10 | 960 |
| 11 | 1920 |
| 12 | 3870 |
| 13 | 7825 |
| 14 | 15650 |
| 15 | 31473 |
| 16 | 63422 |
| 17 | 126844 |
| 18 | 254649 |
| 19 | 509298 |
| 20 | 1021248 |
| 21 | 2050541 |
| 22 | 4101082 |
| 23 | 8219801 |
| 24 | 16490635 |
| 25 | 32981270 |
| 26 | 66071490 |
| 27 | 132455435 |
| 28 | 264910870 |
| 29 | 530485275 |
| 30 | 1060970550 |
| 31 | 2123841570 |
| 32 | 4253619813 |
| 33 | 8507239626 |
| 34 | 17027951548 |
| 35 | 34095896991 |
| 36 | 68191793982 |
| 37 | 136471574881 |
| 38 | 272943149762 |
| 39 | 546144278026 |
| 40 | 1093108792776 |
| 41 | 2186217585552 |
[1,3,6,13,28,56,115,237,474,960,1920,3870,7825, 15650,31473,63422,126844,254649,509298,1021248, 2050541,4101082,8219801,16490635,32981270, 66071490,132455435,264910870,530485275,1060970550, 2123841570,4253619813,8507239626,17027951548, 34095896991,68191793982,136471574881,272943149762, 546144278026,1093108792776,2186217585552] |