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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 1 |
| 3 | 2 |
| 4 | 4 |
| 5 | 6 |
| 6 | 11 |
| 7 | 16 |
| 8 | 28 |
| 9 | 44 |
| 10 | 76 |
| 11 | 124 |
| 12 | 222 |
| 13 | 378 |
| 14 | 685 |
| 15 | 1222 |
| 16 | 2248 |
| 17 | 4110 |
| 18 | 7683 |
| 19 | 14308 |
| 20 | 27010 |
| 21 | 50962 |
| 22 | 96907 |
| 23 | 184408 |
| 24 | 352696 |
| 25 | 675186 |
| 26 | 1296856 |
| 27 | 2493724 |
| 28 | 4806076 |
| 29 | 9272778 |
| 30 | 17920858 |
| 31 | 34669600 |
| 32 | 67159048 |
| 33 | 130216122 |
| 34 | 252745366 |
| 35 | 490984486 |
| 36 | 954637556 |
| 37 | 1857545298 |
| 38 | 3617214679 |
| 39 | 7048675958 |
| 40 | 13744694926 |
| 41 | 26818405350 |
[0,1,2,4,6,11,16,28,44,76,124,222,378,685,1222, 2248,4110,7683,14308,27010,50962,96907,184408, 352696,675186,1296856,2493724,4806076,9272778, 17920858,34669600,67159048,130216122,252745366, 490984486,954637556,1857545298,3617214679, 7048675958,13744694926,26818405350] |