Induction proof verification ##2^{n+2} < (n+1)## for all n ##\geq 6##

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SUMMARY

The discussion confirms the validity of the inequality \(2^{n+2} < (n+1)!\) for all \(n \geq 6\). The proof utilizes mathematical induction, starting with the base case \(n = 6\) where \(256 < 5040\). The inductive hypothesis assumes \(2^{k+2} < (k+1)!\) and demonstrates that \(2^{k+3} < (k+2)!\) holds true by leveraging the factorial growth rate. The conclusion is that the left-hand side grows at a slower rate than the right-hand side as \(n\) increases.

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ciencero
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$2^{n+2} < (n+1)!$ for all n $\geq 6$

Step 1: For n = 6,

$256 < 5040$.

We assume

$2^{k+2} < (k+1)!$

Induction step:

$2 * 2^{k+2} < 2*(k+1)!$

By noting $2*(k+1)! < (k+2)!$

Then $2^{k+3} < (k+2)!$
 
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Looks fine.
n=6 is not the first place where the inequality is true, by the way.
 
ciencero said:
$2^{n+2} < (n+1)!$ for all n $\geq 6$

Step 1: For n = 6,

$256 < 5040$.

We assume

$2^{k+2} < (k+1)!$

Induction step:

$2 * 2^{k+2} < 2*(k+1)!$

By noting $2*(k+1)! < (k+2)!$

Then $2^{k+3} < (k+2)!$
@ciencero, at this site, use double $ characters at each end for standalone LaTeX, or double # characters at each end for inline LaTeX.
 
It seems clear the RH side will eventually dominate. LH is being multiplied by 2 from nth to (n+1)st term while RH side is being multiplied by increasingly larger factors.
 

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