Proving $3^n < (n+3)!$ for all natural numbers $n$ [closed]











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I have the problem:




Prove: $3^n < (n+3)!$ for all natural numbers $n$.




I get to the point,
$$P(k+1) = 3^{k} cdot3 < (k+3)! cdot3 < (k+3)! cdot(k+3)$$

but I am not sure where to go from here.



Help appreciated.










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closed as unclear what you're asking by max_zorn, Shailesh, Lord Shark the Unknown, T. Bongers, user10354138 Nov 27 at 5:22


Please clarify your specific problem or add additional details to highlight exactly what you need. As it's currently written, it’s hard to tell exactly what you're asking. See the How to Ask page for help clarifying this question. If this question can be reworded to fit the rules in the help center, please edit the question.











  • 1




    1) If you are going to delete a question, delete it. Don't just edit so it is unreadable. and 2) Don't delete questions. Just because you now know the answer doesn't mean other people will want to use it.
    – fleablood
    Nov 27 at 3:11






  • 1




    Do not vandalize your question to obfuscate it after posting. It's very rude to the person who bothered to answer.
    – T. Bongers
    Nov 27 at 4:31










  • What on earth are $P$ and $k$?
    – user21820
    yesterday















up vote
-2
down vote

favorite












I have the problem:




Prove: $3^n < (n+3)!$ for all natural numbers $n$.




I get to the point,
$$P(k+1) = 3^{k} cdot3 < (k+3)! cdot3 < (k+3)! cdot(k+3)$$

but I am not sure where to go from here.



Help appreciated.










share|cite|improve this question















closed as unclear what you're asking by max_zorn, Shailesh, Lord Shark the Unknown, T. Bongers, user10354138 Nov 27 at 5:22


Please clarify your specific problem or add additional details to highlight exactly what you need. As it's currently written, it’s hard to tell exactly what you're asking. See the How to Ask page for help clarifying this question. If this question can be reworded to fit the rules in the help center, please edit the question.











  • 1




    1) If you are going to delete a question, delete it. Don't just edit so it is unreadable. and 2) Don't delete questions. Just because you now know the answer doesn't mean other people will want to use it.
    – fleablood
    Nov 27 at 3:11






  • 1




    Do not vandalize your question to obfuscate it after posting. It's very rude to the person who bothered to answer.
    – T. Bongers
    Nov 27 at 4:31










  • What on earth are $P$ and $k$?
    – user21820
    yesterday













up vote
-2
down vote

favorite









up vote
-2
down vote

favorite











I have the problem:




Prove: $3^n < (n+3)!$ for all natural numbers $n$.




I get to the point,
$$P(k+1) = 3^{k} cdot3 < (k+3)! cdot3 < (k+3)! cdot(k+3)$$

but I am not sure where to go from here.



Help appreciated.










share|cite|improve this question















I have the problem:




Prove: $3^n < (n+3)!$ for all natural numbers $n$.




I get to the point,
$$P(k+1) = 3^{k} cdot3 < (k+3)! cdot3 < (k+3)! cdot(k+3)$$

but I am not sure where to go from here.



Help appreciated.







discrete-mathematics






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share|cite|improve this question













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share|cite|improve this question








edited Nov 27 at 4:40









Blue

47.2k870149




47.2k870149










asked Nov 27 at 1:39









cap

83




83




closed as unclear what you're asking by max_zorn, Shailesh, Lord Shark the Unknown, T. Bongers, user10354138 Nov 27 at 5:22


Please clarify your specific problem or add additional details to highlight exactly what you need. As it's currently written, it’s hard to tell exactly what you're asking. See the How to Ask page for help clarifying this question. If this question can be reworded to fit the rules in the help center, please edit the question.






closed as unclear what you're asking by max_zorn, Shailesh, Lord Shark the Unknown, T. Bongers, user10354138 Nov 27 at 5:22


Please clarify your specific problem or add additional details to highlight exactly what you need. As it's currently written, it’s hard to tell exactly what you're asking. See the How to Ask page for help clarifying this question. If this question can be reworded to fit the rules in the help center, please edit the question.










  • 1




    1) If you are going to delete a question, delete it. Don't just edit so it is unreadable. and 2) Don't delete questions. Just because you now know the answer doesn't mean other people will want to use it.
    – fleablood
    Nov 27 at 3:11






  • 1




    Do not vandalize your question to obfuscate it after posting. It's very rude to the person who bothered to answer.
    – T. Bongers
    Nov 27 at 4:31










  • What on earth are $P$ and $k$?
    – user21820
    yesterday














  • 1




    1) If you are going to delete a question, delete it. Don't just edit so it is unreadable. and 2) Don't delete questions. Just because you now know the answer doesn't mean other people will want to use it.
    – fleablood
    Nov 27 at 3:11






  • 1




    Do not vandalize your question to obfuscate it after posting. It's very rude to the person who bothered to answer.
    – T. Bongers
    Nov 27 at 4:31










  • What on earth are $P$ and $k$?
    – user21820
    yesterday








1




1




1) If you are going to delete a question, delete it. Don't just edit so it is unreadable. and 2) Don't delete questions. Just because you now know the answer doesn't mean other people will want to use it.
– fleablood
Nov 27 at 3:11




1) If you are going to delete a question, delete it. Don't just edit so it is unreadable. and 2) Don't delete questions. Just because you now know the answer doesn't mean other people will want to use it.
– fleablood
Nov 27 at 3:11




1




1




Do not vandalize your question to obfuscate it after posting. It's very rude to the person who bothered to answer.
– T. Bongers
Nov 27 at 4:31




Do not vandalize your question to obfuscate it after posting. It's very rude to the person who bothered to answer.
– T. Bongers
Nov 27 at 4:31












What on earth are $P$ and $k$?
– user21820
yesterday




What on earth are $P$ and $k$?
– user21820
yesterday










1 Answer
1






active

oldest

votes

















up vote
0
down vote



accepted










$3^{k} cdot 3 < (k + 3)! cdot 3 < (k+3)!(k + 4) = (k + 4)! = ((k+1)+3)!$



Well $3 < 4 < 4 + k$






share|cite|improve this answer























  • That prove P(k+1)
    – ZAF
    Nov 27 at 1:46


















1 Answer
1






active

oldest

votes








1 Answer
1






active

oldest

votes









active

oldest

votes






active

oldest

votes








up vote
0
down vote



accepted










$3^{k} cdot 3 < (k + 3)! cdot 3 < (k+3)!(k + 4) = (k + 4)! = ((k+1)+3)!$



Well $3 < 4 < 4 + k$






share|cite|improve this answer























  • That prove P(k+1)
    – ZAF
    Nov 27 at 1:46















up vote
0
down vote



accepted










$3^{k} cdot 3 < (k + 3)! cdot 3 < (k+3)!(k + 4) = (k + 4)! = ((k+1)+3)!$



Well $3 < 4 < 4 + k$






share|cite|improve this answer























  • That prove P(k+1)
    – ZAF
    Nov 27 at 1:46













up vote
0
down vote



accepted







up vote
0
down vote



accepted






$3^{k} cdot 3 < (k + 3)! cdot 3 < (k+3)!(k + 4) = (k + 4)! = ((k+1)+3)!$



Well $3 < 4 < 4 + k$






share|cite|improve this answer














$3^{k} cdot 3 < (k + 3)! cdot 3 < (k+3)!(k + 4) = (k + 4)! = ((k+1)+3)!$



Well $3 < 4 < 4 + k$







share|cite|improve this answer














share|cite|improve this answer



share|cite|improve this answer








edited Nov 27 at 1:46

























answered Nov 27 at 1:43









ZAF

4457




4457












  • That prove P(k+1)
    – ZAF
    Nov 27 at 1:46


















  • That prove P(k+1)
    – ZAF
    Nov 27 at 1:46
















That prove P(k+1)
– ZAF
Nov 27 at 1:46




That prove P(k+1)
– ZAF
Nov 27 at 1:46



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