Guest Posted May 1, 2009 Report Share Posted May 1, 2009 Hola! here is a numerical sequence that i just figured out durring 6th period today. 2 - 4 - 6 - 9 - 12 - 16 - ? - ? - ? - ? - ? try to guess the next 5 Quote Link to comment Share on other sites More sharing options...
0 Guest Posted May 1, 2009 Report Share Posted May 1, 2009 Hola! here is a numerical sequence that i just figured out durring 6th period today. 2 - 4 - 6 - 9 - 12 - 16 - ? - ? - ? - ? - ? try to guess the next 5 20-25-30-36-42 Quote Link to comment Share on other sites More sharing options...
0 Guest Posted May 2, 2009 Report Share Posted May 2, 2009 Hola! here is a numerical sequence that i just figured out durring 6th period today. 2 - 4 - 6 - 9 - 12 - 16 - ? - ? - ? - ? - ? try to guess the next 5 20, 25, 30, 36, 42, 49, 56, 64... 3 multiples of 2, the third one is the first of 3 multiples of 3, and it continues like this. This works because the third multiple of any number (like 2) is a multiple of the next number (6=2 times 3) Quote Link to comment Share on other sites More sharing options...
0 Guest Posted May 2, 2009 Report Share Posted May 2, 2009 20, 25, 30, 36, 42, 49, 56, 64... 3 multiples of 2, the third one is the first of 3 multiples of 3, and it continues like this. This works because the third multiple of any number (like 2) is a multiple of the next number (6=2 times 3) both are right but that's not the rule. Quote Link to comment Share on other sites More sharing options...
0 Guest Posted May 3, 2009 Report Share Posted May 3, 2009 both are right but that's not the rule. Add 2 twice consecutively, then add 3 twice consecutively, then add 4 twice consecutively... etc. Quote Link to comment Share on other sites More sharing options...
0 Guest Posted May 4, 2009 Report Share Posted May 4, 2009 Is this the right way to post an answer? just joined, total newbie 2-4-6-9-12-16-20-25-30-36-42-49-56 Hola! here is a numerical sequence that i just figured out durring 6th period today. 2 - 4 - 6 - 9 - 12 - 16 - ? - ? - ? - ? - ? try to guess the next 5 Quote Link to comment Share on other sites More sharing options...
0 Guest Posted May 5, 2009 Report Share Posted May 5, 2009 Add 2 twice consecutively, then add 3 twice consecutively, then add 4 twice consecutively... etc. still, no that isn't it. try to think about powers "Is this the right way to post an answer? just joined, total newbie 2-4-6-9-12-16-20-25-30-36-42-49-56" - clebr8evrtng yes that's right no give me the rule and use a spoiler Quote Link to comment Share on other sites More sharing options...
0 Guest Posted May 5, 2009 Report Share Posted May 5, 2009 still, no that isn't it. try to think about powers "Is this the right way to post an answer? just joined, total newbie 2-4-6-9-12-16-20-25-30-36-42-49-56" - clebr8evrtng yes that's right no give me the rule and use a spoiler For series, "A[1], B[1], A[2], B[2], A[3], B[3], ..." A[n]=n^2+n B[n]=(n+1)^2 Quote Link to comment Share on other sites More sharing options...
0 tiger_lily111 Posted May 5, 2009 Report Share Posted May 5, 2009 I believe the rule isSquare it & add it. 2, 2^2, 2^2 +2, 3^3, 3^3 +3, 4^4, 4^4 +4, 5^5, 5^5 +5, 6^6, 6^6 +6, 7^7, 7^7 +7 Quote Link to comment Share on other sites More sharing options...
0 Guest Posted May 7, 2009 Report Share Posted May 7, 2009 tiger_lily111 and Phatfingers are close but not quite. keep it up guys and gals! Quote Link to comment Share on other sites More sharing options...
0 Guest Posted May 10, 2009 Report Share Posted May 10, 2009 remember keep thinking powers and here is a hint. it had to begin with 2 because if i began with 0 or one it wouldn't work. Quote Link to comment Share on other sites More sharing options...
0 Guest Posted May 11, 2009 Report Share Posted May 11, 2009 I have a few ways to get the answer. See if any are the way your looking for. I'm sure everyone knows the answer is: 20,25,30,36,42. But you want the rule correct? Starting with the 2 you add 2 to get 4, add 2 to get 6, add 3 to get 9, add 3 to get 12, add 4 to get 16, add 4 to get 20, add 5 to get 25, add 5 to get 30, add 6 to get 36, and add 6 to get 42.. If you keep going that way 49, 56, 64 will follow. heres another way of seeing it: 1x2=2 2x2=4 3x2=6 3x3=9 4x3=12 4x4=16 5x4=20 5x5=25 6x5=30 6x6=36 7x6=42 see the pattern there? It works to get 49,56,and 64 and so on.[spoiler='reason #3 ']you said think powers. The only thing I could think up that has to do with powers is: take the square root of every other number in the sequence and you start to see a pattern. So take 4,9,16,25,36,49,64. If you write it on paper its more clear, but basically it goes 2 to the second power, 3 to the second power, 4 to the second power, 5 to the second power, 6 to the second power and continues on. Also if you subtract the number by the square root of that number, you get the previous number in the sequence. (for example take 16, subtract it from its square root of 4 and get the 12 in the sequence.) All three of them methods should continue to follow the same pattern. Idk tho its late. whats up MN!! Quote Link to comment Share on other sites More sharing options...
0 bonanova Posted May 11, 2009 Report Share Posted May 11, 2009 I'd go with James' rule number 2 above as the simplest. But no rule yet explains the minus signs, unless they were used, instead of commas, for separators. Quote Link to comment Share on other sites More sharing options...
0 Guest Posted May 12, 2009 Report Share Posted May 12, 2009 (edited) congratulations James8421!!! you got the answer! yeah i found out how to get from one perfect square to another and decided to make a riddle of it. Good Job guys!! Edited May 12, 2009 by No1slight Quote Link to comment Share on other sites More sharing options...
0 Guest Posted May 12, 2009 Report Share Posted May 12, 2009 so it was 2+ for the first 2 then 3+ for the next two so next 5 are: 20, 25, 30, 36, 42 (i think) Quote Link to comment Share on other sites More sharing options...
0 Guest Posted May 12, 2009 Report Share Posted May 12, 2009 so it was 2+ for the first 2 then 3+ for the next two so next 5 are: 20, 25, 30, 36, 42 (i think) lol not quite right. try to read all the posts (after all this one is only 2 pages long) and you'll find that the answer has been found out by james in his most recent post. Quote Link to comment Share on other sites More sharing options...
0 Guest Posted May 12, 2009 Report Share Posted May 12, 2009 lol not quite right. try to read all the posts (after all this one is only 2 pages long) and you'll find that the answer has been found out by james in his most recent post. i did his first answer was mine Quote Link to comment Share on other sites More sharing options...
0 Guest Posted May 12, 2009 Report Share Posted May 12, 2009 lol not quite right. try to read all the posts (after all this one is only 2 pages long) and you'll find that the answer has been found out by james in his most recent post. Which of James' three answers matched your technique? His third answer seemed to be a pattern of (N^2-N, N^2) where N starts at 2. If N started at 0, that sequence would be: 0, 0, 0, 1, 2, 4, 6, 9, 12, 16, 20, 25, 30, 36, 42, 49, 56, 64, 72, 81, 90, 100 ... Quote Link to comment Share on other sites More sharing options...
0 Guest Posted May 12, 2009 Report Share Posted May 12, 2009 I'd go with James' rule number 2 above as the simplest. But no rule yet explains the minus signs, unless they were used, instead of commas, for separators. Yes. It helps to flip the first product from "1x2=2" to "2x1=2". Then, you can see a sort of lightning-bolt pattern (down, right, down) to the numbers. Pretty clever technique. Quote Link to comment Share on other sites More sharing options...
0 Guest Posted May 13, 2009 Report Share Posted May 13, 2009 Yes. It helps to flip the first product from "1x2=2" to "2x1=2". Then, you can see a sort of lightning-bolt pattern (down, right, down) to the numbers. Pretty clever technique. I found a similar pattern described as: trunc(N*N/4) Quote Link to comment Share on other sites More sharing options...
Question
Guest
Hola! here is a numerical sequence that i just figured out durring 6th period today.
2 - 4 - 6 - 9 - 12 - 16 - ? - ? - ? - ? - ?
try to guess the next 5
Link to comment
Share on other sites
19 answers to this question
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.