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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 1 |
| 5 | 1 |
| 6 | 2 |
| 7 | 3 |
| 8 | 6 |
| 9 | 9 |
| 10 | 13 |
| 11 | 18 |
| 12 | 26 |
| 13 | 35 |
| 14 | 50 |
| 15 | 66 |
| 16 | 90 |
| 17 | 117 |
| 18 | 155 |
| 19 | 199 |
| 20 | 260 |
| 21 | 331 |
| 22 | 425 |
| 23 | 537 |
| 24 | 681 |
| 25 | 852 |
| 26 | 1070 |
| 27 | 1328 |
| 28 | 1652 |
| 29 | 2038 |
| 30 | 2517 |
| 31 | 3083 |
| 32 | 3783 |
| 33 | 4609 |
| 34 | 5618 |
| 35 | 6811 |
| 36 | 8257 |
| 37 | 9959 |
| 38 | 12014 |
| 39 | 14429 |
| 40 | 17322 |
| 41 | 20721 |
| 42 | 24771 |
| 43 | 29515 |
| 44 | 35147 |
| 45 | 41730 |
| 46 | 49507 |
| 47 | 58585 |
| 48 | 69267 |
| 49 | 81705 |
[0,0,0,1,1,2,3,6,9,13,18,26,35,50,66,90,117,155, 199,260,331,425,537,681,852,1070,1328,1652,2038, 2517,3083,3783,4609,5618,6811,8257,9959,12014, 14429,17322,20721,24771,29515,35147,41730,49507, 58585,69267,81705] |