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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 6 |
| 4 | 13 |
| 5 | 25 |
| 6 | 50 |
| 7 | 94 |
| 8 | 178 |
| 9 | 328 |
| 10 | 601 |
| 11 | 1083 |
| 12 | 1940 |
| 13 | 3436 |
| 14 | 6047 |
| 15 | 10558 |
| 16 | 18326 |
| 17 | 31614 |
| 18 | 54265 |
| 19 | 92683 |
| 20 | 157626 |
| 21 | 266985 |
| 22 | 450580 |
| 23 | 757851 |
| 24 | 1270757 |
| 25 | 2124721 |
| 26 | 3543318 |
| 27 | 5894831 |
| 28 | 9785243 |
| 29 | 16210036 |
| 30 | 26802756 |
| 31 | 44240560 |
| 32 | 72906608 |
| 33 | 119969779 |
[1,3,6,13,25,50,94,178,328,601,1083,1940,3436, 6047,10558,18326,31614,54265,92683,157626,266985, 450580,757851,1270757,2124721,3543318,5894831, 9785243,16210036,26802756,44240560,72906608, 119969779] |