P(1) Count=1 排列
C(1) Count=1 组合
CP(1)Count=1 所有组合下的排列总和——根话题的需求

P(2) Count=2
C(2) Count=3
CP(2)Count=4

P(3) Count=6
C(3) Count=7
CP(3)Count=15

P(4) Count=24
C(4) Count=15
CP(4)Count=64

P(5) Count=120
C(5) Count=31
CP(5)Count=325

P(6) Count=720
C(6) Count=63
CP(6)Count=1956

P(7) Count=5040
C(7) Count=127
CP(7)Count=13699

P(8) Count=40320
C(8) Count=255
CP(8)Count=109600

P(9) Count=362880
C(9) Count=511
CP(9)Count=986409

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