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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 0 |
| 6 | 1 |
| 7 | 2 |
| 8 | 3 |
| 9 | 4 |
| 10 | 5 |
| 11 | 6 |
| 12 | 8 |
| 13 | 10 |
| 14 | 15 |
| 15 | 20 |
| 16 | 30 |
| 17 | 40 |
| 18 | 58 |
| 19 | 76 |
| 20 | 106 |
| 21 | 140 |
| 22 | 191 |
| 23 | 252 |
| 24 | 344 |
| 25 | 454 |
| 26 | 613 |
| 27 | 814 |
| 28 | 1091 |
| 29 | 1442 |
| 30 | 1926 |
| 31 | 2538 |
| 32 | 3368 |
| 33 | 4432 |
| 34 | 5852 |
| 35 | 7678 |
| 36 | 10107 |
| 37 | 13222 |
| 38 | 17337 |
| 39 | 22636 |
| 40 | 29582 |
| 41 | 38518 |
| 42 | 50195 |
| 43 | 65198 |
| 44 | 84712 |
| 45 | 109784 |
| 46 | 142254 |
| 47 | 183924 |
| 48 | 237742 |
| 49 | 306688 |
[1,0,0,0,0,0,1,2,3,4,5,6,8,10,15,20,30,40,58,76, 106,140,191,252,344,454,613,814,1091,1442,1926, 2538,3368,4432,5852,7678,10107,13222,17337,22636, 29582,38518,50195,65198,84712,109784,142254, 183924,237742,306688] |