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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 3 |
| 6 | 6 |
| 7 | 13 |
| 8 | 26 |
| 9 | 47 |
| 10 | 81 |
| 11 | 140 |
| 12 | 253 |
| 13 | 482 |
| 14 | 949 |
| 15 | 1875 |
| 16 | 3666 |
| 17 | 7088 |
| 18 | 13614 |
| 19 | 26100 |
| 20 | 50082 |
| 21 | 96246 |
| 22 | 185131 |
| 23 | 356123 |
| 24 | 684758 |
| 25 | 1316197 |
| 26 | 2530257 |
| 27 | 4868019 |
| 28 | 9378335 |
| 29 | 18096921 |
| 30 | 34974646 |
| 31 | 67669905 |
| 32 | 130998912 |
| 33 | 253565649 |
| 34 | 490501587 |
| 35 | 947992195 |
| 36 | 1830664188 |
| 37 | 3533571444 |
[1,0,1,1,1,3,6,13,26,47,81,140,253,482,949,1875, 3666,7088,13614,26100,50082,96246,185131,356123, 684758,1316197,2530257,4868019,9378335,18096921, 34974646,67669905,130998912,253565649,490501587, 947992195,1830664188,3533571444] |