※ 引述《WhiteBoss (一個人玩~~~~  )》之銘言:
: 若有一數x,滿足x^2+5和x^2-5都是平方數...求x=?
不存在這樣的X
pf: We know that (n+1)^2-n^2=2n+1.
Thus, if n is greater than 5 the difference of two concecutive squares
are greater than 10.
Also, if n=5 then n^2=25 and (n+1)^2=36.
Obviously 31, 20, 41 are not squares.
Therefore we have proven our conjecture.
BTW 王巍興你在那個地方看到這個問題
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