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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 4 |
| 5 | 8 |
| 6 | 18 |
| 7 | 43 |
| 8 | 102 |
| 9 | 247 |
| 10 | 617 |
| 11 | 1564 |
| 12 | 4003 |
| 13 | 10355 |
| 14 | 27051 |
| 15 | 71225 |
| 16 | 188743 |
| 17 | 503111 |
| 18 | 1348301 |
| 19 | 3630294 |
| 20 | 9815159 |
| 21 | 26637436 |
| 22 | 72540432 |
| 23 | 198162708 |
| 24 | 542875096 |
| 25 | 1491126550 |
| 26 | 4105602719 |
| 27 | 11329408543 |
| 28 | 31328137525 |
| 29 | 86795258650 |
| 30 | 240898943969 |
| 31 | 669730499207 |
| 32 | 1864855943748 |
[1,1,2,4,8,18,43,102,247,617,1564,4003,10355, 27051,71225,188743,503111,1348301,3630294,9815159, 26637436,72540432,198162708,542875096,1491126550, 4105602719,11329408543,31328137525,86795258650, 240898943969,669730499207,1864855943748] |