Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Next number in a sequence

  1. Mar 31, 2007 #1
    What is the next number in the sequence? 2, 3, 10, 15, 26, 35, 50, ?
     
  2. jcsd
  3. Mar 31, 2007 #2

    cristo

    User Avatar
    Staff Emeritus
    Science Advisor

    Is this some sort of homework question?
     
  4. Mar 31, 2007 #3
    63
    1st..(1*1)+1 odd
    2nd (2*2)-1 even
    3rd (3*3)+1 odd
    ....
    8th (8*8)-1 even
     
  5. Feb 17, 2008 #4
    yeah i got 63 too, but in a different way i think.
    basically, the differences between them respectively, are 1, 7, 5, 11, 9, and 15.
    divide it like this: 1, 7, 5, and 11, 9, 15
    then take the sum of the last two digits in the first set, and subtract the first. so in this case, 7 + 5 -1.
    you get 11, which is the next difference.
    do this with the second set of 11, 9, and 15 and you'll get 13 as the next difference, meaning that 50 + 13 should be the next number.
    that's how i got 63.
    let me know what you guys think.
     
  6. Mar 8, 2008 #5
    This is what I was thinking as well. I suspect it.anoopk's solution was probably the original intention. Seems a bit less random.
     
    Last edited: Mar 8, 2008
  7. Nov 2, 2008 #6
    i got 63, too, but a different way, i got it by 2+1=3, add 6 to the one, 3:7=10, subtract 2 from the 7, add the number you grt<5> 15, add the 6 to 5 get 11 add 11 get 26 subtract 2 get 9 add 9 get 35 add 6 get 15 add 15 to 35 get 50 subtract 2 get 13 add 13 to 50 get 63 yay i win
     
  8. Nov 2, 2008 #7
    i got it a different way: =2+1=3 add 6 to 1 get 7 add 7 get 10 subtract 2 get 5 add 5 get 15 add 6 get 11 add 11 get 26 subtract 2 get 9 add 9 get 35 add 6 get 15 add 15 get 50 subtract to add 13 get 63 =[] this is the immature way to do it but i got it done in 3 minutes and im only 12...
     
  9. Nov 2, 2008 #8
    that was too easy
     
  10. Nov 26, 2008 #9
    10 10 11 12 15 16 21
     
  11. Nov 26, 2008 #10
    S(n) = 2, 3, 10, 15, 26, 35, 50, 63, .... , (n2) - (-1)n


    T(n) = (n2) - (-1)n
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?



Similar Discussions: Next number in a sequence
  1. Next Number (Replies: 12)

  2. Next Number? (Replies: 16)

Loading...