✔ 最佳答案
Sol
[1,2,3,4,6,8,12,16,24]
=[2,3,4,6,8,12,16,24]
=2*[1,3,2,4,6,8,12]
=2*[3,2,4,6,8,12]
=4*[3,1,2,3,4,6]
=4*[3,2,3,4,6]
=8*[3,1,3,2,3]
=8*[3,3,2,3]
=16*[3,3,1,3]
=48
a=48p,p為正整數
a不為7的倍數
a不為9的倍數
1008=48*21
(a,1008)=(48p,1008=48(p,21)
21=1*21=3*7
(p,21)=1 or (p,21)=3 or (p,21)=7 or (p,21)=21
(1)
(p,21)=1
(a,1008)=48
(2)
(p,21)=3
(a,1008)=144
144|a
9|a(不合)
(3)
(p,21)=7
(a,1008)=336
7|a(不合)
(4)
(p,21)=21
(a,1008)=1008
7|a(不合)
綜合(1),(2),(3),(4)
(a,1008)=48