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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 1 |
| 5 | 2 |
| 6 | 3 |
| 7 | 6 |
| 8 | 13 |
| 9 | 26 |
| 10 | 52 |
| 11 | 108 |
| 12 | 226 |
| 13 | 472 |
| 14 | 993 |
| 15 | 2106 |
| 16 | 4485 |
| 17 | 9586 |
| 18 | 20576 |
| 19 | 44332 |
| 20 | 95814 |
| 21 | 207688 |
| 22 | 451438 |
| 23 | 983736 |
| 24 | 2148618 |
| 25 | 4702976 |
| 26 | 10314672 |
| 27 | 22664452 |
| 28 | 49887084 |
| 29 | 109985772 |
| 30 | 242854669 |
| 31 | 537004218 |
| 32 | 1189032613 |
| 33 | 2636096922 |
| 34 | 5851266616 |
| 35 | 13002628132 |
| 36 | 28925389870 |
| 37 | 64412505472 |
| 38 | 143576017410 |
[0,0,0,0,1,2,3,6,13,26,52,108,226,472,993,2106, 4485,9586,20576,44332,95814,207688,451438,983736, 2148618,4702976,10314672,22664452,49887084, 109985772,242854669,537004218,1189032613, 2636096922,5851266616,13002628132,28925389870, 64412505472,143576017410] |