Find common term for this sequence

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The discussion revolves around finding a common term for the sequence 6/(12 + 1), 1/(22 + 1), 6/(32 + 1), and 1/(42 + 1). Participants suggest using the mod function to handle the alternating numerators of 6 and 1. There is mention of a special number that, when raised to integer powers, can produce the desired alternating behavior. The conversation emphasizes the need to identify a formula for the nth term of the sequence. Understanding the mod function is highlighted as a potential solution for managing the alternation in the sequence.
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Homework Statement


6 /(12 + 1), 1/(22 + 1),6/(32 + 1),1/(42 + 1)

Homework Equations


none

The Attempt at a Solution


I suspect this is not that hard, I get the denominators but the numerator alternates so I though I would need 6 to be the base of a power that alternates between 0 and 1 but I can't think of anything :/
 
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Are you trying to find a formula for the nth term in the sequence?

You can handle the alternation between 1 and 6 by using the mod function, expressing things in mod 2.

Or, there's a special number that, when raised to the power of integer ##n##, gives alternating behavior of the type you seek. What number is that?
 
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andrewkirk said:
Are you trying to find a formula for the nth term in the sequence?

You can handle the alternation between 1 and 6 by using the mod function, expressing things in mod 2.

Or, there's a special number that, when raised to the power of integer ##n##, gives alternating behavior of the type you seek. What number is that?
yes that's what I'm trying to do
I've never heard of a mod function:/ but i'll google it. A number that alternates between one and zero? can't think of one, hint?
 
NihalRi said:
A number that alternates between one and zero?
The number doesn't alternate. Its powers do ('power' as in multiplying a number by itself an integer number of times). Every time we increase the power/index/exponent by 1, the result switches from one of the possible values to the other. Also, the two possible values are not 1 and 0.

The link for mod function is a hyperlink in my post above (blue text).
 
I tried to combine those 2 formulas but it didn't work. I tried using another case where there are 2 red balls and 2 blue balls only so when combining the formula I got ##\frac{(4-1)!}{2!2!}=\frac{3}{2}## which does not make sense. Is there any formula to calculate cyclic permutation of identical objects or I have to do it by listing all the possibilities? Thanks
Since ##px^9+q## is the factor, then ##x^9=\frac{-q}{p}## will be one of the roots. Let ##f(x)=27x^{18}+bx^9+70##, then: $$27\left(\frac{-q}{p}\right)^2+b\left(\frac{-q}{p}\right)+70=0$$ $$b=27 \frac{q}{p}+70 \frac{p}{q}$$ $$b=\frac{27q^2+70p^2}{pq}$$ From this expression, it looks like there is no greatest value of ##b## because increasing the value of ##p## and ##q## will also increase the value of ##b##. How to find the greatest value of ##b##? Thanks
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