What number comes next in this sequence?











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$4, 15, 13, 7, 22, -1, 31, -9, 40, -17, 49$.



What comes next? The answer is $-25$, but why?






sequences-and-series pattern-recognition







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  • 9




    My answer is 42. The reason is that I like the number 42. And there is no one who can prove me wrong. That being said, if I were to try to read the mind of whoever made this problem, I would look at every other term.
    – Arthur
    2 hours ago








  • 1




    Any finite sequence of integers can be continued any way you like. Sometimes there are patterns that suggest that one continuation is more natural than another. I see no such pattern here. If you [edit' the question to tell us where the sequence comes from we may be able to hlep. Otherwise the question will probably be closed.
    – Ethan Bolker
    2 hours ago















up vote
1
down vote

favorite
1












$4, 15, 13, 7, 22, -1, 31, -9, 40, -17, 49$.



What comes next? The answer is $-25$, but why?






sequences-and-series pattern-recognition







share|cite|improve this question







New contributor




stackofhay42 is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
















  • 9




    My answer is 42. The reason is that I like the number 42. And there is no one who can prove me wrong. That being said, if I were to try to read the mind of whoever made this problem, I would look at every other term.
    – Arthur
    2 hours ago








  • 1




    Any finite sequence of integers can be continued any way you like. Sometimes there are patterns that suggest that one continuation is more natural than another. I see no such pattern here. If you [edit' the question to tell us where the sequence comes from we may be able to hlep. Otherwise the question will probably be closed.
    – Ethan Bolker
    2 hours ago













up vote
1
down vote

favorite
1









up vote
1
down vote

favorite
1






1





$4, 15, 13, 7, 22, -1, 31, -9, 40, -17, 49$.



What comes next? The answer is $-25$, but why?






sequences-and-series pattern-recognition







share|cite|improve this question







New contributor




stackofhay42 is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.











$4, 15, 13, 7, 22, -1, 31, -9, 40, -17, 49$.



What comes next? The answer is $-25$, but why?






sequences-and-series pattern-recognition




sequences-and-series pattern-recognition






share|cite|improve this question







New contributor




stackofhay42 is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.











share|cite|improve this question







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stackofhay42 is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
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asked 2 hours ago









stackofhay42

1163




1163




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  • 9




    My answer is 42. The reason is that I like the number 42. And there is no one who can prove me wrong. That being said, if I were to try to read the mind of whoever made this problem, I would look at every other term.
    – Arthur
    2 hours ago








  • 1




    Any finite sequence of integers can be continued any way you like. Sometimes there are patterns that suggest that one continuation is more natural than another. I see no such pattern here. If you [edit' the question to tell us where the sequence comes from we may be able to hlep. Otherwise the question will probably be closed.
    – Ethan Bolker
    2 hours ago














  • 9




    My answer is 42. The reason is that I like the number 42. And there is no one who can prove me wrong. That being said, if I were to try to read the mind of whoever made this problem, I would look at every other term.
    – Arthur
    2 hours ago








  • 1




    Any finite sequence of integers can be continued any way you like. Sometimes there are patterns that suggest that one continuation is more natural than another. I see no such pattern here. If you [edit' the question to tell us where the sequence comes from we may be able to hlep. Otherwise the question will probably be closed.
    – Ethan Bolker
    2 hours ago








9




9




My answer is 42. The reason is that I like the number 42. And there is no one who can prove me wrong. That being said, if I were to try to read the mind of whoever made this problem, I would look at every other term.
– Arthur
2 hours ago






My answer is 42. The reason is that I like the number 42. And there is no one who can prove me wrong. That being said, if I were to try to read the mind of whoever made this problem, I would look at every other term.
– Arthur
2 hours ago






1




1




Any finite sequence of integers can be continued any way you like. Sometimes there are patterns that suggest that one continuation is more natural than another. I see no such pattern here. If you [edit' the question to tell us where the sequence comes from we may be able to hlep. Otherwise the question will probably be closed.
– Ethan Bolker
2 hours ago




Any finite sequence of integers can be continued any way you like. Sometimes there are patterns that suggest that one continuation is more natural than another. I see no such pattern here. If you [edit' the question to tell us where the sequence comes from we may be able to hlep. Otherwise the question will probably be closed.
– Ethan Bolker
2 hours ago










2 Answers
2






active

oldest

votes

















up vote
10
down vote



accepted










Break up the sequence into the even ordered terms and odd ordered.






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  • 2




    Wow! I was looking for some very complicated patterns, and it is actually so easy.
    – Mark
    2 hours ago


















up vote
3
down vote














  • Firs observation, first term and second term add up to 19, third and fourth add to 20, fifth and sixth add to 21 and so on..


According to that, the the next number is $49+x = 24 implies x = -25$




  • Second observation, second and third terms add to 28, the fourth and fifth add to 29 and so on...


Therefore, you can generate the next number using these two observations anywhere in the sequence.



I know this is not the best way to predict the next number. However, it is not a bad try.



:)






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    2 Answers
    2






    active

    oldest

    votes








    2 Answers
    2






    active

    oldest

    votes









    active

    oldest

    votes






    active

    oldest

    votes








    up vote
    10
    down vote



    accepted










    Break up the sequence into the even ordered terms and odd ordered.






    share|cite|improve this answer

















    • 2




      Wow! I was looking for some very complicated patterns, and it is actually so easy.
      – Mark
      2 hours ago















    up vote
    10
    down vote



    accepted










    Break up the sequence into the even ordered terms and odd ordered.






    share|cite|improve this answer

















    • 2




      Wow! I was looking for some very complicated patterns, and it is actually so easy.
      – Mark
      2 hours ago













    up vote
    10
    down vote



    accepted







    up vote
    10
    down vote



    accepted






    Break up the sequence into the even ordered terms and odd ordered.






    share|cite|improve this answer












    Break up the sequence into the even ordered terms and odd ordered.







    share|cite|improve this answer












    share|cite|improve this answer



    share|cite|improve this answer










    answered 2 hours ago









    TurlocTheRed

    723110




    723110








    • 2




      Wow! I was looking for some very complicated patterns, and it is actually so easy.
      – Mark
      2 hours ago














    • 2




      Wow! I was looking for some very complicated patterns, and it is actually so easy.
      – Mark
      2 hours ago








    2




    2




    Wow! I was looking for some very complicated patterns, and it is actually so easy.
    – Mark
    2 hours ago




    Wow! I was looking for some very complicated patterns, and it is actually so easy.
    – Mark
    2 hours ago










    up vote
    3
    down vote














    • Firs observation, first term and second term add up to 19, third and fourth add to 20, fifth and sixth add to 21 and so on..


    According to that, the the next number is $49+x = 24 implies x = -25$




    • Second observation, second and third terms add to 28, the fourth and fifth add to 29 and so on...


    Therefore, you can generate the next number using these two observations anywhere in the sequence.



    I know this is not the best way to predict the next number. However, it is not a bad try.



    :)






    share|cite|improve this answer



























      up vote
      3
      down vote














      • Firs observation, first term and second term add up to 19, third and fourth add to 20, fifth and sixth add to 21 and so on..


      According to that, the the next number is $49+x = 24 implies x = -25$




      • Second observation, second and third terms add to 28, the fourth and fifth add to 29 and so on...


      Therefore, you can generate the next number using these two observations anywhere in the sequence.



      I know this is not the best way to predict the next number. However, it is not a bad try.



      :)






      share|cite|improve this answer

























        up vote
        3
        down vote










        up vote
        3
        down vote










        • Firs observation, first term and second term add up to 19, third and fourth add to 20, fifth and sixth add to 21 and so on..


        According to that, the the next number is $49+x = 24 implies x = -25$




        • Second observation, second and third terms add to 28, the fourth and fifth add to 29 and so on...


        Therefore, you can generate the next number using these two observations anywhere in the sequence.



        I know this is not the best way to predict the next number. However, it is not a bad try.



        :)






        share|cite|improve this answer















        • Firs observation, first term and second term add up to 19, third and fourth add to 20, fifth and sixth add to 21 and so on..


        According to that, the the next number is $49+x = 24 implies x = -25$




        • Second observation, second and third terms add to 28, the fourth and fifth add to 29 and so on...


        Therefore, you can generate the next number using these two observations anywhere in the sequence.



        I know this is not the best way to predict the next number. However, it is not a bad try.



        :)







        share|cite|improve this answer














        share|cite|improve this answer



        share|cite|improve this answer








        edited 1 hour ago

























        answered 2 hours ago









        Maged Saeed

        527315




        527315






















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