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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 0 |
| 2 | 0 |
| 3 | 2 |
| 4 | 3 |
| 5 | 7 |
| 6 | 12 |
| 7 | 22 |
| 8 | 42 |
| 9 | 78 |
| 10 | 141 |
| 11 | 264 |
| 12 | 494 |
| 13 | 936 |
| 14 | 1778 |
| 15 | 3397 |
| 16 | 6511 |
| 17 | 12523 |
| 18 | 24149 |
| 19 | 46713 |
| 20 | 90531 |
| 21 | 175865 |
| 22 | 342166 |
| 23 | 666693 |
| 24 | 1300774 |
| 25 | 2541095 |
| 26 | 4969243 |
| 27 | 9727574 |
| 28 | 19059405 |
| 29 | 37374922 |
| 30 | 73346919 |
| 31 | 144042828 |
| 32 | 283064512 |
| 33 | 556601031 |
| 34 | 1095087423 |
[0,0,0,2,3,7,12,22,42,78,141,264,494,936,1778, 3397,6511,12523,24149,46713,90531,175865,342166, 666693,1300774,2541095,4969243,9727574,19059405, 37374922,73346919,144042828,283064512,556601031, 1095087423] |