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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 4 |
| 3 | 12 |
| 4 | 30 |
| 5 | 72 |
| 6 | 186 |
| 7 | 464 |
| 8 | 1122 |
| 9 | 2646 |
| 10 | 6050 |
| 11 | 13408 |
| 12 | 28726 |
| 13 | 58844 |
| 14 | 114418 |
| 15 | 209176 |
| 16 | 355926 |
| 17 | 559108 |
| 18 | 800636 |
| 19 | 1014616 |
| 20 | 1086948 |
| 21 | 930728 |
| 22 | 595740 |
| 23 | 256688 |
| 24 | 58948 |
[1,4,12,30,72,186,464,1122,2646,6050,13408,28726, 58844,114418,209176,355926,559108,800636,1014616, 1086948,930728,595740,256688,58948] |