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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 2 |
| 3 | 6 |
| 4 | 12 |
| 5 | 26 |
| 6 | 54 |
| 7 | 112 |
| 8 | 227 |
| 9 | 460 |
| 10 | 930 |
| 11 | 1877 |
| 12 | 3780 |
| 13 | 7606 |
| 14 | 15291 |
| 15 | 30720 |
| 16 | 61680 |
| 17 | 123790 |
| 18 | 248346 |
| 19 | 498073 |
| 20 | 998643 |
| 21 | 2001826 |
| 22 | 4011942 |
| 23 | 8039082 |
| 24 | 16106127 |
| 25 | 32263876 |
| 26 | 64623350 |
| 27 | 129424237 |
| 28 | 259179060 |
| 29 | 518975214 |
| 30 | 1039104990 |
| 31 | 2080374784 |
| 32 | 4164816771 |
| 33 | 8337289456 |
| 34 | 16689015778 |
[0,1,2,6,12,26,54,112,227,460,930,1877,3780,7606, 15291,30720,61680,123790,248346,498073,998643, 2001826,4011942,8039082,16106127,32263876, 64623350,129424237,259179060,518975214,1039104990, 2080374784,4164816771,8337289456,16689015778] |