There is a sequence An for a positive integer n such that wh

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There is a sequence An for a positive integer n such that when An-2 is divided by An-1 the remainder is An. If A3=6, A4=0, which of the following can be the value of A1?

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A. 48
B. 50
C. 52
D. 56
E. 58


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by Max@Math Revolution » Wed Apr 27, 2016 12:39 am
There is a sequence An for a positive integer n such that when An-2 is divided by An-1 the remainder is An. If A3=6, A4=0, which of the following can be the value of A1?

A. 48
B. 50
C. 52
D. 56
E. 58


==> If n=4, A2=A3Q+A4=6Q+0=6Q is derived.
If n=3, from A1=A2P+A3=6QP+6=6(QP+1), it becomes always a multiple of 6.
Thus, the answer is A.