单选题
If n is a positive integer, then n(n+1)(n+2) is
(A) even only when n is even
(B) even only when n is odd
(C) odd whenever n is odd
(D) divisible by 3 only when n is odd
(E) divisible by 4 whenever n is even
A
B
C
D
E
【正确答案】
E
【答案解析】
[解析] n(n+1)(n+2)是三个连续正整数的乘积,而根据连续整数的性质可知,无论n取何数,他们三个数中一定有一个偶数,且一定有一个数是3的倍数,所以n(n+1)(n+2)一定是偶数,且能被3整除;若n是偶数时,则n+2也一定是偶数,所以此时n(n+1)(n+2)也一定能被4整除。
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