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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 3 |
| 4 | 6 |
| 5 | 10 |
| 6 | 20 |
| 7 | 36 |
| 8 | 72 |
| 9 | 135 |
| 10 | 272 |
| 11 | 528 |
| 12 | 1048 |
| 13 | 2080 |
| 14 | 4160 |
| 15 | 8242 |
| 16 | 16500 |
| 17 | 32895 |
| 18 | 65750 |
| 19 | 131328 |
| 20 | 262612 |
| 21 | 524733 |
| 22 | 1049600 |
| 23 | 2098176 |
| 24 | 4195930 |
| 25 | 8390620 |
| 26 | 16781312 |
| 27 | 33558177 |
| 28 | 67116876 |
| 29 | 134225920 |
| 30 | 268450626 |
| 31 | 536887270 |
[1,2,3,6,10,20,36,72,135,272,528,1048,2080,4160, 8242,16500,32895,65750,131328,262612,524733, 1049600,2098176,4195930,8390620,16781312,33558177, 67116876,134225920,268450626,536887270] |