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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 4 |
| 4 | 9 |
| 5 | 20 |
| 6 | 45 |
| 7 | 101 |
| 8 | 228 |
| 9 | 514 |
| 10 | 1160 |
| 11 | 2617 |
| 12 | 5906 |
| 13 | 13327 |
| 14 | 30075 |
| 15 | 67868 |
| 16 | 153156 |
| 17 | 345621 |
| 18 | 779953 |
| 19 | 1760094 |
| 20 | 3971951 |
| 21 | 8963378 |
| 22 | 20227382 |
| 23 | 45646511 |
| 24 | 103009086 |
| 25 | 232457449 |
| 26 | 524579615 |
| 27 | 1183802763 |
| 28 | 2671451479 |
| 29 | 6028582814 |
| 30 | 13604518396 |
| 31 | 30700900429 |
| 32 | 69281782713 |
[1,1,2,4,9,20,45,101,228,514,1160,2617,5906,13327, 30075,67868,153156,345621,779953,1760094,3971951, 8963378,20227382,45646511,103009086,232457449, 524579615,1183802763,2671451479,6028582814, 13604518396,30700900429,69281782713] |