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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 5 |
| 6 | 2 |
| 7 | 14 |
| 8 | 13 |
| 9 | 31 |
| 10 | 66 |
| 11 | 77 |
| 12 | 240 |
| 13 | 286 |
| 14 | 722 |
| 15 | 1226 |
| 16 | 2141 |
| 17 | 4760 |
| 18 | 7268 |
| 19 | 16473 |
| 20 | 27716 |
| 21 | 54615 |
| 22 | 106217 |
| 23 | 187818 |
| 24 | 388084 |
| 25 | 685830 |
| 26 | 1370162 |
| 27 | 2569351 |
| 28 | 4849538 |
| 29 | 9526355 |
| 30 | 17598392 |
| 31 | 34694301 |
| 32 | 65152925 |
| 33 | 125679731 |
| 34 | 242019753 |
| 35 | 459049449 |
| 36 | 893614680 |
| 37 | 1695840536 |
[1,0,1,1,1,5,2,14,13,31,66,77,240,286,722,1226, 2141,4760,7268,16473,27716,54615,106217,187818, 388084,685830,1370162,2569351,4849538,9526355, 17598392,34694301,65152925,125679731,242019753, 459049449,893614680,1695840536] |