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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 7 |
| 4 | 9 |
| 5 | 63 |
| 6 | 168 |
| 7 | 322 |
| 8 | 1518 |
| 9 | 1680 |
| 10 | 10878 |
| 11 | 17575 |
| 12 | 70224 |
| 13 | 97524 |
| 14 | 224846 |
| 15 | 612360 |
| 16 | 15473807 |
| 17 | 61011223 |
| 18 | 108384553 |
| 19 | 137308589 |
| 20 | 999208250 |
| 21 | 1497820158 |
| 22 | 22377473780 |
| 23 | 238092971076 |
| 24 | 316419292600 |
| 25 | 23931257472314 |
[1,3,7,9,63,168,322,1518,1680,10878,17575,70224, 97524,224846,612360,15473807,61011223,108384553, 137308589,999208250,1497820158,22377473780, 238092971076,316419292600,23931257472314] |