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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 0 |
| 3 | 0 |
| 4 | 2 |
| 5 | 4 |
| 6 | 7 |
| 7 | 14 |
| 8 | 23 |
| 9 | 38 |
| 10 | 68 |
| 11 | 118 |
| 12 | 207 |
| 13 | 369 |
| 14 | 665 |
| 15 | 1198 |
| 16 | 2219 |
| 17 | 4081 |
| 18 | 7629 |
| 19 | 14266 |
| 20 | 26923 |
| 21 | 50874 |
| 22 | 96781 |
| 23 | 184270 |
| 24 | 352447 |
| 25 | 674971 |
| 26 | 1296453 |
| 27 | 2493302 |
| 28 | 4805387 |
| 29 | 9272067 |
| 30 | 17919557 |
| 31 | 34668386 |
| 32 | 67156731 |
| 33 | 130213775 |
| 34 | 252741245 |
[1,1,0,0,2,4,7,14,23,38,68,118,207,369,665,1198, 2219,4081,7629,14266,26923,50874,96781,184270, 352447,674971,1296453,2493302,4805387,9272067, 17919557,34668386,67156731,130213775,252741245] |