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| n | a(n) |
|---|---|
| 1 | 18 |
| 2 | 20 |
| 3 | 70 |
| 4 | 104 |
| 5 | 464 |
| 6 | 1952 |
| 7 | 45356 |
| 8 | 91388 |
| 9 | 130304 |
| 10 | 254012 |
| 11 | 388076 |
| 12 | 437745 |
| 13 | 522752 |
| 14 | 8382464 |
| 15 | 134193152 |
[18,20,70,104,464,1952,45356,91388,130304,254012, 388076,437745,522752,8382464,134193152] |