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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 0 |
| 2 | 0 |
| 3 | 2 |
| 4 | 3 |
| 5 | 5 |
| 6 | 9 |
| 7 | 17 |
| 8 | 30 |
| 9 | 57 |
| 10 | 105 |
| 11 | 199 |
| 12 | 373 |
| 13 | 701 |
| 14 | 1345 |
| 15 | 2575 |
| 16 | 4954 |
| 17 | 9562 |
| 18 | 18509 |
| 19 | 35916 |
| 20 | 69837 |
| 21 | 136010 |
| 22 | 265251 |
| 23 | 518118 |
| 24 | 1013282 |
| 25 | 1983707 |
| 26 | 3887580 |
| 27 | 7625434 |
| 28 | 14969119 |
| 29 | 29407328 |
| 30 | 57811961 |
| 31 | 113724176 |
| 32 | 223843323 |
| 33 | 440828855 |
| 34 | 868596930 |
[0,0,0,2,3,5,9,17,30,57,105,199,373,701,1345,2575, 4954,9562,18509,35916,69837,136010,265251,518118, 1013282,1983707,3887580,7625434,14969119,29407328, 57811961,113724176,223843323,440828855,868596930] |