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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 3 |
| 5 | 6 |
| 6 | 10 |
| 7 | 20 |
| 8 | 36 |
| 9 | 72 |
| 10 | 137 |
| 11 | 274 |
| 12 | 543 |
| 13 | 1086 |
| 14 | 2219 |
| 15 | 4438 |
| 16 | 9285 |
| 17 | 18570 |
| 18 | 39587 |
| 19 | 79174 |
| 20 | 171369 |
| 21 | 342738 |
| 22 | 751236 |
| 23 | 1502472 |
| 24 | 3328218 |
| 25 | 6656436 |
| 26 | 14878455 |
| 27 | 29756910 |
| 28 | 67030785 |
| 29 | 134061570 |
| 30 | 304036170 |
| 31 | 608072340 |
| 32 | 1387247580 |
| 33 | 2774495160 |
[1,1,2,3,6,10,20,36,72,137,274,543,1086,2219,4438, 9285,18570,39587,79174,171369,342738,751236, 1502472,3328218,6656436,14878455,29756910, 67030785,134061570,304036170,608072340,1387247580, 2774495160] |