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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 1 |
| 3 | 1 |
| 4 | 2 |
| 5 | 3 |
| 6 | 6 |
| 7 | 11 |
| 8 | 22 |
| 9 | 43 |
| 10 | 87 |
| 11 | 176 |
| 12 | 362 |
| 13 | 748 |
| 14 | 1560 |
| 15 | 3270 |
| 16 | 6897 |
| 17 | 14613 |
| 18 | 31104 |
| 19 | 66459 |
| 20 | 142518 |
| 21 | 306603 |
| 22 | 661572 |
| 23 | 1431363 |
| 24 | 3104619 |
| 25 | 6749390 |
| 26 | 14704387 |
| 27 | 32098729 |
| 28 | 70198656 |
| 29 | 153785705 |
| 30 | 337443785 |
| 31 | 741551614 |
| 32 | 1631910081 |
| 33 | 3596083215 |
[1,0,1,1,2,3,6,11,22,43,87,176,362,748,1560,3270, 6897,14613,31104,66459,142518,306603,661572, 1431363,3104619,6749390,14704387,32098729, 70198656,153785705,337443785,741551614,1631910081, 3596083215] |