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| n | a(n) |
|---|---|
| 0 | -1 |
| 1 | 0 |
| 2 | 0 |
| 3 | 1 |
| 4 | 3 |
| 5 | 6 |
| 6 | 13 |
| 7 | 23 |
| 8 | 44 |
| 9 | 75 |
| 10 | 135 |
| 11 | 226 |
| 12 | 393 |
| 13 | 651 |
| 14 | 1108 |
| 15 | 1823 |
| 16 | 3059 |
| 17 | 5010 |
| 18 | 8325 |
| 19 | 13591 |
| 20 | 22428 |
| 21 | 36531 |
| 22 | 59983 |
| 23 | 97538 |
| 24 | 159569 |
| 25 | 259155 |
| 26 | 422820 |
| 27 | 686071 |
| 28 | 1117083 |
| 29 | 1811346 |
| 30 | 2944813 |
| 31 | 4772543 |
| 32 | 7750124 |
| 33 | 12555435 |
| 34 | 20371095 |
| 35 | 32992066 |
| 36 | 53494233 |
| 37 | 86617371 |
| 38 | 140373748 |
[-1,0,0,1,3,6,13,23,44,75,135,226,393,651,1108, 1823,3059,5010,8325,13591,22428,36531,59983,97538, 159569,259155,422820,686071,1117083,1811346, 2944813,4772543,7750124,12555435,20371095, 32992066,53494233,86617371,140373748] |