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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 0 |
| 6 | 0 |
| 7 | 0 |
| 8 | 0 |
| 9 | 0 |
| 10 | 1 |
| 11 | 9 |
| 12 | 53 |
| 13 | 251 |
| 14 | 1043 |
| 15 | 3961 |
| 16 | 14102 |
| 17 | 47816 |
| 18 | 156129 |
| 19 | 494769 |
| 20 | 1530583 |
| 21 | 4642490 |
| 22 | 13853571 |
| 23 | 40779959 |
| 24 | 118666510 |
| 25 | 341938083 |
| 26 | 977028128 |
| 27 | 2771407719 |
| 28 | 7811504825 |
| 29 | 21895173627 |
| 30 | 61069528116 |
| 31 | 169590519864 |
| 32 | 469117076770 |
[0,0,0,0,0,0,0,0,0,1,9,53,251,1043,3961,14102, 47816,156129,494769,1530583,4642490,13853571, 40779959,118666510,341938083,977028128,2771407719, 7811504825,21895173627,61069528116,169590519864, 469117076770] |