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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 8 |
| 3 | 24 |
| 4 | 64 |
| 5 | 161 |
| 6 | 385 |
| 7 | 899 |
| 8 | 2053 |
| 9 | 4617 |
| 10 | 10257 |
| 11 | 22559 |
| 12 | 49208 |
| 13 | 106601 |
| 14 | 229571 |
| 15 | 491884 |
| 16 | 1049258 |
| 17 | 2229509 |
| 18 | 4721020 |
| 19 | 9966072 |
| 20 | 20980260 |
| 21 | 44056840 |
| 22 | 92306470 |
| 23 | 192998784 |
| 24 | 402769716 |
| 25 | 839084537 |
| 26 | 1745260723 |
| 27 | 3624707293 |
| 28 | 7517790835 |
| 29 | 15572342341 |
| 30 | 32218220725 |
| 31 | 66583540100 |
[2,8,24,64,161,385,899,2053,4617,10257,22559, 49208,106601,229571,491884,1049258,2229509, 4721020,9966072,20980260,44056840,92306470, 192998784,402769716,839084537,1745260723, 3624707293,7517790835,15572342341,32218220725, 66583540100] |