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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 4 |
| 4 | 12 |
| 5 | 32 |
| 6 | 85 |
| 7 | 217 |
| 8 | 539 |
| 9 | 1316 |
| 10 | 3146 |
| 11 | 7374 |
| 12 | 16969 |
| 13 | 38387 |
| 14 | 85452 |
| 15 | 187456 |
| 16 | 405659 |
| 17 | 866759 |
| 18 | 1830086 |
| 19 | 3821072 |
| 20 | 7894447 |
| 21 | 16148593 |
| 22 | 32723147 |
| 23 | 65719405 |
| 24 | 130871128 |
| 25 | 258513076 |
| 26 | 506724988 |
| 27 | 985968770 |
| 28 | 1904992841 |
| 29 | 3655873294 |
| 30 | 6970687150 |
| 31 | 13208622956 |
| 32 | 24879427889 |
| 33 | 46593011280 |
| 34 | 86773920240 |
| 35 | 160742462714 |
| 36 | 296227087942 |
| 37 | 543183754454 |
| 38 | 991213989213 |
[1,2,4,12,32,85,217,539,1316,3146,7374,16969, 38387,85452,187456,405659,866759,1830086,3821072, 7894447,16148593,32723147,65719405,130871128, 258513076,506724988,985968770,1904992841, 3655873294,6970687150,13208622956,24879427889, 46593011280,86773920240,160742462714,296227087942, 543183754454,991213989213] |