4~9这六个数可以组成几个四位数？

    6*5*4*3=360(个)4567,4576,4657,4675,4756,47655674,5647,5476,5467,5746,57646457,6475,6574,6547,6745,67547456,7465,7546,7564,7654,76454568,4586,4685,4658,4856,48655684,5648,5486,5468,5846,58646458,6485,6584,6548,6854,68458456,8465,8564,8546,8654,86454569,4596,4695,4659,4965,49565469,5496,5694,5649,5964,59466459,6495,6594,6549,6945,69549456,9465,9564,9546,9654,96454578,4587,4785,4758,4857,48755478,5487,5748,5784,5874,58477458,7485,7854,7845,7584,75488745,8754,8475,8457,8547,85744579,4597,4759,4795,4957,49755794,5749,5479,5497,5947,59477459,7495,7549,7594,7945,79549457,9475,9547,9574,9745,97544589,4598,4895,4859,4958,49855489,5498,5894,5849,5984,59488459,8495,8549,8594,8945,89549854,9845,9485,9458,9584,95484678,4687,4786,4768,4876,48676478,6487,6748,6784,6874,68477468,7486,7684,7648,7846,78648746,8764,8467,8476,8647,86744679,4697,4796,4769,4976,49676479,6497,6794,6749,6974,69477469,7496,7694,7649,7964,79469746,9764,9476,9467,9647,96744689,4698,4896,4869,4986,49686489,6498,6849,6894,6984,69488469,8496,8694,8649,8964,89469846,9864,9486,9468,9684,96484789,4798,4987,4978,4879,48977489,7498,7849,7894,7984,79488479,8497,8974,8947,8794,87499874,9847,9748,9784,9478,94875678,5687,5876,5867,5786,57687568,7586,7658,7685,7856,78656785,6758,6587,6578,6875,68578756,8765,8567,8576,8657,86755679,5697,5967,5976,5769,57966759,6795,6957,6975,6579,65977569,7596,7659,7695,7956,79659756,9765,9567,9576,9675,96575689,5698,5968,5986,5896,58696895,6859,6958,6985,6589,65988956,8965,8596,8569,8659,86959568,9586,9658,9685,9856,98655789,5798,5987,5978,5879,58977859,7895,7985,7958,7589,75988759,8795,8579,8597,8957,89759875,9857,9578,9587,9785,97586789,6798,6897,6879,6987,69787896,7869,7968,7986,7689,76988796,8769,8967,8976,8679,86979876,9867,9687,9678,9786,9768。
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