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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 0 |
| 2 | 1 |
| 3 | 7 |
| 4 | 27 |
| 5 | 81 |
| 6 | 213 |
| 7 | 519 |
| 8 | 1207 |
| 9 | 2725 |
| 10 | 6033 |
| 11 | 13179 |
| 12 | 28515 |
| 13 | 61257 |
| 14 | 130861 |
| 15 | 278287 |
| 16 | 589551 |
| 17 | 1244877 |
| 18 | 2621097 |
| 19 | 5504643 |
| 20 | 11533915 |
| 21 | 24116785 |
| 22 | 50331141 |
| 23 | 104857047 |
| 24 | 218103207 |
| 25 | 452984181 |
| 26 | 939523393 |
| 27 | 1946156299 |
| 28 | 4026531027 |
| 29 | 8321498265 |
| 30 | 17179868253 |
| 31 | 35433479199 |
| 32 | 73014442975 |
| 33 | 150323854237 |
[0,0,1,7,27,81,213,519,1207,2725,6033,13179,28515, 61257,130861,278287,589551,1244877,2621097, 5504643,11533915,24116785,50331141,104857047, 218103207,452984181,939523393,1946156299, 4026531027,8321498265,17179868253,35433479199, 73014442975,150323854237] |