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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 3 |
| 5 | 6 |
| 6 | 12 |
| 7 | 20 |
| 8 | 35 |
| 9 | 60 |
| 10 | 114 |
| 11 | 207 |
| 12 | 375 |
| 13 | 671 |
| 14 | 1213 |
| 15 | 2180 |
| 16 | 3954 |
| 17 | 7139 |
| 18 | 12892 |
| 19 | 23250 |
| 20 | 41996 |
| 21 | 75793 |
| 22 | 136891 |
| 23 | 247133 |
| 24 | 446211 |
| 25 | 805505 |
| 26 | 1454390 |
| 27 | 2625744 |
| 28 | 4740788 |
| 29 | 8559108 |
| 30 | 15453182 |
| 31 | 27899503 |
| 32 | 50371415 |
| 33 | 90942627 |
| 34 | 164192549 |
| 35 | 296440115 |
[1,1,1,1,3,6,12,20,35,60,114,207,375,671,1213, 2180,3954,7139,12892,23250,41996,75793,136891, 247133,446211,805505,1454390,2625744,4740788, 8559108,15453182,27899503,50371415,90942627, 164192549,296440115] |