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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 4 |
| 4 | 16 |
| 5 | 36 |
| 6 | 64 |
| 7 | 218 |
| 8 | 1104 |
| 9 | 2112 |
| 10 | 4096 |
| 11 | 9608 |
| 12 | 90416 |
| 13 | 266496 |
| 14 | 528384 |
| 15 | 1048576 |
| 16 | 1540944 |
| 17 | 30194176 |
| 18 | 135032832 |
| 19 | 269500416 |
| 20 | 537919488 |
| 21 | 1073741824 |
[1,3,4,16,36,64,218,1104,2112,4096,9608,90416, 266496,528384,1048576,1540944,30194176,135032832, 269500416,537919488,1073741824] |