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Edward
Joined: 02 Dec 2004Posts: 2
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Posted: Thu Dec 02, 2004 4:48 pm Post subject: Number theory( factorial )
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Let
Find all such that is a square number.
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Soarer
Frequent VisitorJoined: 18 Jan 2004Posts: 213
Location: Hong Kong
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Posted: Thu Dec 02, 2004 5:42 pm Post subject:
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For n>=5, A(n)=4!+3!+2!+1=3(mod 5) Since 3 is quadratic nonresidue, n
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