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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 0 |
| 6 | 0 |
| 7 | 1 |
| 8 | 1 |
| 9 | 3 |
| 10 | 6 |
| 11 | 15 |
| 12 | 29 |
| 13 | 67 |
| 14 | 139 |
| 15 | 310 |
| 16 | 667 |
| 17 | 1480 |
| 18 | 3244 |
| 19 | 7241 |
| 20 | 16104 |
| 21 | 36192 |
| 22 | 81435 |
| 23 | 184452 |
| 24 | 418870 |
| 25 | 955860 |
| 26 | 2187664 |
| 27 | 5025990 |
| 28 | 11580130 |
| 29 | 26765230 |
| 30 | 62027433 |
| 31 | 144133676 |
| 32 | 335731381 |
| 33 | 783859852 |
| 34 | 1834104934 |
| 35 | 4300433063 |
| 36 | 10102854473 |
| 37 | 23778351222 |
[1,0,0,0,0,0,1,1,3,6,15,29,67,139,310,667,1480, 3244,7241,16104,36192,81435,184452,418870,955860, 2187664,5025990,11580130,26765230,62027433, 144133676,335731381,783859852,1834104934, 4300433063,10102854473,23778351222] |