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#1 2007-09-22 22:34:10
- tommy20
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Sequence
We have sequence, wich is define by the conditions:
Decide if exist any integer number
and#2 2019-05-19 02:39:03
- Alg Num Theory
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- Registered: 2017-11-24
- Posts: 693
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Re: Sequence
It is clear that none of the terms in the sequence is divisible by 5. For
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Similarly none of the terms is divisible by 3, for
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It follows that
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i.e. consecutive terms are coprime; also
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i.e. alternate terms are coprime as well.
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Since a₁ = 1, k =1 fits the bill. And since the sequence is clearly strictly increasing, it is the only one that does.
Me, or the ugly man, whatever (3,3,6)
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