From 1, 2, 3, 4, ..., 2000, a total of 2000 positive integers, how many numbers can be taken at most, so that for any three numbers a, b, c (a<b<c) in the number taken out , all have ab≠c.
从1，2，3，4，…，2000共2000个正整数中，最多能取出多少个数，使得对于取出来的数中的任意三个数a、b、c(a＜b＜c)，都有ab≠c．
<gadget id="calculator">2_000 - 45</gadget>
<output>1_955</output>

<gadget id="calculator">1_955 + 1</gadget>
<output>1_956</output>

<gadget id="calculator">1_956 + 1</gadget>
<output>1_957</output>

<result>1_957</result>