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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 4 |
| 4 | 11 |
| 5 | 29 |
| 6 | 97 |
| 7 | 300 |
| 8 | 1077 |
| 9 | 3634 |
| 10 | 13653 |
| 11 | 49031 |
| 12 | 190864 |
| 13 | 716619 |
| 14 | 2864542 |
| 15 | 11113948 |
| 16 | 45338516 |
| 17 | 180423941 |
| 18 | 748010246 |
| 19 | 3037549738 |
| 20 | 12759948361 |
| 21 | 52676833687 |
| 22 | 223710004285 |
| 23 | 936214898900 |
| 24 | 4012733348896 |
| 25 | 16986312988164 |
| 26 | 73381258658937 |
| 27 | 313666205814135 |
| 28 | 1364316375158136 |
| 29 | 5880681766872382 |
[1,1,2,4,11,29,97,300,1077,3634,13653,49031, 190864,716619,2864542,11113948,45338516,180423941, 748010246,3037549738,12759948361,52676833687, 223710004285,936214898900,4012733348896, 16986312988164,73381258658937,313666205814135, 1364316375158136,5880681766872382] |