Is the integer n odd?
(1) n is divisible by 3.
(2) 2n is divisible by twice as many positive integers as n.
Statement (1) ALONE is sufficient, but statement (2) alone is not sufficient.
Statement (2) ALONE is sufficient, but statement (1) alone is not sufficient.
BOTH statements TOGETHER are sufficient, but NEITHER statement ALONE is sufficient.
EACH statement ALONE is sufficient.
Statements (1) and (2) TOGETHER are NOT sufficient.
条件2:2n的因数是n因数的两倍
以n=15 n有4个因子,1,3,5,15; 2n=30,有8个,1,2,3,6,5,10,15,30。
如果n=6的话,n有4个:1,2,3,6。 2n有1,2,3,4,6,12。 n不能为偶数 sufficient
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