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| n | a(n) |
|---|---|
| 1 | -2 |
| 2 | -1 |
| 3 | 0 |
| 4 | 0 |
| 5 | 2 |
| 6 | 3 |
| 7 | 5 |
| 8 | 8 |
| 9 | 15 |
| 10 | 24 |
| 11 | 40 |
| 12 | 72 |
| 13 | 119 |
| 14 | 212 |
| 15 | 360 |
| 16 | 633 |
| 17 | 1128 |
| 18 | 1989 |
| 19 | 3580 |
| 20 | 6386 |
| 21 | 11537 |
| 22 | 20897 |
| 23 | 37980 |
| 24 | 69354 |
| 25 | 127336 |
| 26 | 234054 |
| 27 | 431877 |
| 28 | 799754 |
| 29 | 1484440 |
| 30 | 2763961 |
| 31 | 5156791 |
| 32 | 9644970 |
| 33 | 18080775 |
| 34 | 33959344 |
| 35 | 63902732 |
| 36 | 120474951 |
| 37 | 227515953 |
| 38 | 430345298 |
| 39 | 815241632 |
[-2,-1,0,0,2,3,5,8,15,24,40,72,119,212,360,633, 1128,1989,3580,6386,11537,20897,37980,69354, 127336,234054,431877,799754,1484440,2763961, 5156791,9644970,18080775,33959344,63902732, 120474951,227515953,430345298,815241632] |