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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 6 |
| 4 | 13 |
| 5 | 31 |
| 6 | 64 |
| 7 | 129 |
| 8 | 249 |
| 9 | 470 |
| 10 | 869 |
| 11 | 1583 |
| 12 | 2848 |
| 13 | 5073 |
| 14 | 8961 |
| 15 | 15718 |
| 16 | 27405 |
| 17 | 47535 |
| 18 | 82080 |
| 19 | 141169 |
| 20 | 241945 |
| 21 | 413366 |
| 22 | 704261 |
| 23 | 1196831 |
| 24 | 2029248 |
| 25 | 3433441 |
| 26 | 5798209 |
| 27 | 9774534 |
| 28 | 16451149 |
| 29 | 27646975 |
| 30 | 46397824 |
[1,1,6,13,31,64,129,249,470,869,1583,2848,5073, 8961,15718,27405,47535,82080,141169,241945,413366, 704261,1196831,2029248,3433441,5798209,9774534, 16451149,27646975,46397824] |