Prove the identity with Stirling numbers.

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For arbitrary integer $m, t, s<n$ prove the identity
$$
sum_i=s+1^n(i!)^2 left n atop iright left m atop iright binomsibinomti=0,
$$
here $displaystyle left n atop iright$ is the Stirling numbers of the second kind.



I come across by accident to the identity as secondary result.
I have checked it for many values, it is true. What about a proof in the general case?







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    Note that $binomsi=0$ if $i>s$.
    – Markus Scheuer
    Jul 16 at 16:45














up vote
1
down vote

favorite












For arbitrary integer $m, t, s<n$ prove the identity
$$
sum_i=s+1^n(i!)^2 left n atop iright left m atop iright binomsibinomti=0,
$$
here $displaystyle left n atop iright$ is the Stirling numbers of the second kind.



I come across by accident to the identity as secondary result.
I have checked it for many values, it is true. What about a proof in the general case?







share|cite|improve this question

















  • 1




    Note that $binomsi=0$ if $i>s$.
    – Markus Scheuer
    Jul 16 at 16:45












up vote
1
down vote

favorite









up vote
1
down vote

favorite











For arbitrary integer $m, t, s<n$ prove the identity
$$
sum_i=s+1^n(i!)^2 left n atop iright left m atop iright binomsibinomti=0,
$$
here $displaystyle left n atop iright$ is the Stirling numbers of the second kind.



I come across by accident to the identity as secondary result.
I have checked it for many values, it is true. What about a proof in the general case?







share|cite|improve this question













For arbitrary integer $m, t, s<n$ prove the identity
$$
sum_i=s+1^n(i!)^2 left n atop iright left m atop iright binomsibinomti=0,
$$
here $displaystyle left n atop iright$ is the Stirling numbers of the second kind.



I come across by accident to the identity as secondary result.
I have checked it for many values, it is true. What about a proof in the general case?









share|cite|improve this question












share|cite|improve this question




share|cite|improve this question








edited Jul 16 at 16:46









Tiwa Aina

2,576319




2,576319









asked Jul 16 at 16:40









Leox

5,0921323




5,0921323







  • 1




    Note that $binomsi=0$ if $i>s$.
    – Markus Scheuer
    Jul 16 at 16:45












  • 1




    Note that $binomsi=0$ if $i>s$.
    – Markus Scheuer
    Jul 16 at 16:45







1




1




Note that $binomsi=0$ if $i>s$.
– Markus Scheuer
Jul 16 at 16:45




Note that $binomsi=0$ if $i>s$.
– Markus Scheuer
Jul 16 at 16:45










1 Answer
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Since $s + 1 leq i leq n$, we see that $i>s , , , forall s < n$. Hence $binomsi=0$. But each term of your sum is the product of $binomsi$ and other values, which means each term will be zero. So the entire sum will be zero.






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    1 Answer
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    active

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    1 Answer
    1






    active

    oldest

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    active

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    up vote
    2
    down vote



    accepted










    Since $s + 1 leq i leq n$, we see that $i>s , , , forall s < n$. Hence $binomsi=0$. But each term of your sum is the product of $binomsi$ and other values, which means each term will be zero. So the entire sum will be zero.






    share|cite|improve this answer



























      up vote
      2
      down vote



      accepted










      Since $s + 1 leq i leq n$, we see that $i>s , , , forall s < n$. Hence $binomsi=0$. But each term of your sum is the product of $binomsi$ and other values, which means each term will be zero. So the entire sum will be zero.






      share|cite|improve this answer

























        up vote
        2
        down vote



        accepted







        up vote
        2
        down vote



        accepted






        Since $s + 1 leq i leq n$, we see that $i>s , , , forall s < n$. Hence $binomsi=0$. But each term of your sum is the product of $binomsi$ and other values, which means each term will be zero. So the entire sum will be zero.






        share|cite|improve this answer















        Since $s + 1 leq i leq n$, we see that $i>s , , , forall s < n$. Hence $binomsi=0$. But each term of your sum is the product of $binomsi$ and other values, which means each term will be zero. So the entire sum will be zero.







        share|cite|improve this answer















        share|cite|improve this answer



        share|cite|improve this answer








        edited Jul 16 at 17:02


























        answered Jul 16 at 16:51









        Tiwa Aina

        2,576319




        2,576319






















             

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