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| n | a(n) |
|---|---|
| 1 | 4 |
| 2 | 4 |
| 3 | 8 |
| 4 | 12 |
| 5 | 18 |
| 6 | 40 |
| 7 | 94 |
| 8 | 184 |
| 9 | 358 |
| 10 | 760 |
| 11 | 1594 |
| 12 | 3220 |
| 13 | 6574 |
| 14 | 13636 |
| 15 | 28078 |
| 16 | 57460 |
| 17 | 118090 |
| 18 | 243232 |
| 19 | 499846 |
| 20 | 1026496 |
| 21 | 2110462 |
| 22 | 4339696 |
| 23 | 8918722 |
| 24 | 18329596 |
| 25 | 37680070 |
| 26 | 77455324 |
| 27 | 159200278 |
| 28 | 327229276 |
| 29 | 672635458 |
| 30 | 1382602264 |
| 31 | 2841890926 |
| 32 | 5841485128 |
[4,4,8,12,18,40,94,184,358,760,1594,3220,6574, 13636,28078,57460,118090,243232,499846,1026496, 2110462,4339696,8918722,18329596,37680070, 77455324,159200278,327229276,672635458,1382602264, 2841890926,5841485128] |