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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 1 |
| 3 | 0 |
| 4 | 2 |
| 5 | 2 |
| 6 | 7 |
| 7 | 16 |
| 8 | 40 |
| 9 | 101 |
| 10 | 246 |
| 11 | 615 |
| 12 | 1504 |
| 13 | 3724 |
| 14 | 9147 |
| 15 | 22567 |
| 16 | 55541 |
| 17 | 136884 |
| 18 | 337128 |
| 19 | 830628 |
| 20 | 2046145 |
| 21 | 5040932 |
| 22 | 12418320 |
| 23 | 30593281 |
| 24 | 75367352 |
| 25 | 185670647 |
| 26 | 457405836 |
| 27 | 1126836394 |
| 28 | 2776001211 |
| 29 | 6838779857 |
| 30 | 16847579205 |
| 31 | 41504619640 |
| 32 | 102248123906 |
| 33 | 251891939366 |
| 34 | 620544865783 |
| 35 | 1528734638988 |
| 36 | 3766092860744 |
[0,1,0,2,2,7,16,40,101,246,615,1504,3724,9147, 22567,55541,136884,337128,830628,2046145,5040932, 12418320,30593281,75367352,185670647,457405836, 1126836394,2776001211,6838779857,16847579205, 41504619640,102248123906,251891939366, 620544865783,1528734638988,3766092860744] |