Can Every Positive Integer Sequence Contain Only Composite Numbers?

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The discussion revolves around proving that for every positive integer n, there exist n consecutive composite integers. The hint suggests starting with the expression (n+1)! + 2. Participants explain that each term in the sequence, starting from (n+1)! + 2, is composite because it is divisible by integers from 2 to n+1. There is some confusion regarding the divisibility of these terms, prompting requests for clarification. The thread also raises a concern about whether this is a homework question, indicating it may not belong in the current forum.
NightFire
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Hey everyone I am new in this forum, and it looks great ! :)
i have this problem to prove this question.id really appreciate our help for this one:

Prove that for every positive integer n,there are n consecutive composite integers.
Theres a the hint in the question that says; consider the n consecutive integers starting with (n+1)! + 2

thanks
for ur help
Roy
 
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Okay, (n+1)!+ 2 is composite because it is divisible by 2. (do you see why?)

(n+1)!+ 3 is composite because it is divisible by 3.

(n+1)!+ 4 is composite because it is divisible by 4.

etc.
 
HallsofIvy said:
Okay, (n+1)!+ 2 is composite because it is divisible by 2. (do you see why?)

(n+1)!+ 3 is composite because it is divisible by 3.

(n+1)!+ 4 is composite because it is divisible by 4.

etc.

i don't see why it is divisible by 2, would you like to explain it please?
much appreciated
 
Last edited:
Are you familiar with the factorial?
k!=k*(k-1)*(k-2)*...*3*2*1

Do you now see why it is divisible by 2?
 
This thread doesn't belong in this forum.

Is this a homework question? If so, this really should be in the "Homework/Coursework Questions" forum.
 
Question: A clock's minute hand has length 4 and its hour hand has length 3. What is the distance between the tips at the moment when it is increasing most rapidly?(Putnam Exam Question) Answer: Making assumption that both the hands moves at constant angular velocities, the answer is ## \sqrt{7} .## But don't you think this assumption is somewhat doubtful and wrong?

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