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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 1 |
| 3 | 2 |
| 4 | 2 |
| 5 | 4 |
| 6 | 6 |
| 7 | 9 |
| 8 | 14 |
| 9 | 27 |
| 10 | 36 |
| 11 | 69 |
| 12 | 94 |
| 13 | 178 |
| 14 | 308 |
| 15 | 589 |
| 16 | 908 |
| 17 | 1540 |
| 18 | 2814 |
| 19 | 5158 |
| 20 | 9210 |
| 21 | 16732 |
| 22 | 29392 |
| 23 | 55109 |
| 24 | 101120 |
| 25 | 179654 |
| 26 | 332130 |
| 27 | 625928 |
| 28 | 1136814 |
| 29 | 2120399 |
| 30 | 3963166 |
| 31 | 7377931 |
| 32 | 13878622 |
| 33 | 25958590 |
| 34 | 48421044 |
| 35 | 92163237 |
| 36 | 173672988 |
| 37 | 325098134 |
| 38 | 617741968 |
| 39 | 1177573074 |
| 40 | 2221353224 |
| 41 | 4222570054 |
[0,1,2,2,4,6,9,14,27,36,69,94,178,308,589,908, 1540,2814,5158,9210,16732,29392,55109,101120, 179654,332130,625928,1136814,2120399,3963166, 7377931,13878622,25958590,48421044,92163237, 173672988,325098134,617741968,1177573074, 2221353224,4222570054] |