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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 1 |
| 4 | 3 |
| 5 | 5 |
| 6 | 13 |
| 7 | 27 |
| 8 | 59 |
| 9 | 125 |
| 10 | 257 |
| 11 | 534 |
| 12 | 1094 |
| 13 | 2244 |
| 14 | 4607 |
| 15 | 9407 |
| 16 | 19164 |
| 17 | 38939 |
| 18 | 79154 |
| 19 | 160473 |
| 20 | 325213 |
| 21 | 658940 |
| 22 | 1332598 |
| 23 | 2694009 |
| 24 | 5440236 |
| 25 | 10973874 |
| 26 | 22135366 |
| 27 | 44644593 |
| 28 | 89989907 |
| 29 | 181374472 |
| 30 | 365371286 |
| 31 | 734959945 |
[0,0,1,3,5,13,27,59,125,257,534,1094,2244,4607, 9407,19164,38939,79154,160473,325213,658940, 1332598,2694009,5440236,10973874,22135366, 44644593,89989907,181374472,365371286,734959945] |