grey cells Posted March 24, 2008 Report Share Posted March 24, 2008 Try solving this number sequence: One I made myself with my fav ingredients. Find the missing number: 2 , 5 , 11 , _ , 137 ,..... Reveal hidden contents play with the bases Quote Link to comment Share on other sites More sharing options...
0 grey cells Posted April 21, 2008 Author Report Share Posted April 21, 2008 Nikyma said: Reveal hidden contents he had it with 17? Reveal hidden contents Nikyma , You got it. Kudos to Nikyma. The answer is 17 . But I am still waiting for the explanation. Quote Link to comment Share on other sites More sharing options...
0 Nikyma Posted April 21, 2008 Report Share Posted April 21, 2008 grey cells said: Reveal hidden contents Nikyma , You got it. Kudos to Nikyma. The answer is 17 . But I am still waiting for the explanation. I'll let Noct know, I just didn't want you to be sad that everyone gave up Quote Link to comment Share on other sites More sharing options...
0 grey cells Posted April 21, 2008 Author Report Share Posted April 21, 2008 Nikyma said: I'll let Noct know, I just didn't want you to be sad that everyone gave up Thanks for the encouragement and replies , Nikyma. And thanks to the good ol' advice from LIS . Still waiting for the explanation though. Quote Link to comment Share on other sites More sharing options...
0 Nikyma Posted April 21, 2008 Report Share Posted April 21, 2008 I'll tell you what my thinking was when I said 23. 2,5,11,__, 137 2+3=5, 5+6=11, 11+12=23, 23+24=47 (which, not understanding bases & binary, I assumed was equal to 137) Quote Link to comment Share on other sites More sharing options...
0 Nikyma Posted April 21, 2008 Report Share Posted April 21, 2008 For 17, I'd have to go with Noct on the "every other prime" idea. But, I don't understand the jump to 137? Quote Link to comment Share on other sites More sharing options...
0 grey cells Posted April 21, 2008 Author Report Share Posted April 21, 2008 (edited) Nikyma said: I'll tell you what my thinking was when I said 23. 2,5,11,__, 137 2+3=5, 5+6=11, 11+12=23, 23+24=47 (which, not understanding bases & binary, I assumed was equal to 137) Good logical reasoning , Nikyma. But as you have said 47 is not 137. EDIT : Just saw your other post . If it was every other alternate prime number , it would have been too easy . I hope now that the answer is known , someone will solve the reasoning part. Edited April 21, 2008 by grey cells Quote Link to comment Share on other sites More sharing options...
0 grey cells Posted April 23, 2008 Author Report Share Posted April 23, 2008 Waiting for the explanation. This one's easy . So I am not giving the explanation . The answer is 17.(for those who don't want to go through previous posts). Quote Link to comment Share on other sites More sharing options...
0 Guest Posted April 23, 2008 Report Share Posted April 23, 2008 grey cells said: Waiting for the explanation. This one's easy . So I am not giving the explanation . The answer is 17.(for those who don't want to go through previous posts). Please post the next number in the sequence. Let's see if someone gets the logic. Quote Link to comment Share on other sites More sharing options...
0 grey cells Posted April 23, 2008 Author Report Share Posted April 23, 2008 (edited) esjohnson said: Please post the next number in the sequence. Let's see if someone gets the logic. Seems like a good idea . OK here goes. Reveal hidden contents 2 , 5 , 11 , 17 , 137 , 149 , 173 , .... Hope now it is clearer. Reveal hidden contents In binary : 1=0001 Edited April 23, 2008 by grey cells Quote Link to comment Share on other sites More sharing options...
0 Guest Posted April 23, 2008 Report Share Posted April 23, 2008 grey cells said: Seems like a good idea . OK here goes. Reveal hidden contents 2 , 5 , 11 , 17 , 137 , 149 , 173 , .... Hope now it is clearer. Reveal hidden contents In binary : 1=0001 Lets wait and watch Quote Link to comment Share on other sites More sharing options...
0 Guest Posted April 23, 2008 Report Share Posted April 23, 2008 I did notice one thing, and I think I'm on the right track, but not all the way there yet. Reveal hidden contents If you list the numbers in order like this.... 2 5 11 17 137 149 173 but in binary, they make this... 00000010 00000101 00001011 00010001 10001001 10010101 10101101 From this you can notice that each line is only different from it's previous line by exactly 3 digits every time. I guess the pattern would then be to change 3 digits and still be prime. If this rule sticks, I think it means the next number would be 197. Quote Link to comment Share on other sites More sharing options...
0 grey cells Posted April 23, 2008 Author Report Share Posted April 23, 2008 Artificial I said: I did notice one thing, and I think I'm on the right track, but not all the way there yet. Reveal hidden contents If you list the numbers in order like this.... 2 5 11 17 137 149 173 but in binary, they make this... 00000010 00000101 00001011 00010001 10001001 10010101 10101101 From this you can notice that each line is only different from it's previous line by exactly 3 digits every time. I guess the pattern would then be to change 3 digits and still be prime. If this rule sticks, I think it means the next number would be 197. Reveal hidden contents observation , AI . It definitely looks that way . But the next number , according to my reasoning is incidently not 197. But your representation of 8 bits is spot-on. Quote Link to comment Share on other sites More sharing options...
0 Guest Posted April 23, 2008 Report Share Posted April 23, 2008 grey cells said: Reveal hidden contents observation , AI . It definitely looks that way . But the next number , according to my reasoning is incidently not 197. But your representation of 8 bits is spot-on. Reveal hidden contents Is it higher or lower than 197? Quote Link to comment Share on other sites More sharing options...
0 grey cells Posted April 23, 2008 Author Report Share Posted April 23, 2008 Artificial I said: Reveal hidden contents Is it higher or lower than 197? Reveal hidden contents Lower than 197 . And another hint is no need for any binary operations , not even binary addition , sub. That's why I said it was easy. Quote Link to comment Share on other sites More sharing options...
0 akaslickster Posted April 23, 2008 Report Share Posted April 23, 2008 Reveal hidden contents 144 Quote Link to comment Share on other sites More sharing options...
0 Guest Posted April 23, 2008 Report Share Posted April 23, 2008 I thought you said that this sequence combined two of your favourite things; prime numbers and binary. Quote Link to comment Share on other sites More sharing options...
0 grey cells Posted April 23, 2008 Author Report Share Posted April 23, 2008 Artificial I said: I thought you said that this sequence combined two of your favourite things; prime numbers and binary. Yes , it definitely does. Quote Link to comment Share on other sites More sharing options...
0 grey cells Posted April 23, 2008 Author Report Share Posted April 23, 2008 (edited) akaslickster said: Reveal hidden contents 144 Nope . Reveal hidden contents is not 144. If you have an explanation please post it. Edited April 23, 2008 by grey cells Quote Link to comment Share on other sites More sharing options...
0 grey cells Posted April 23, 2008 Author Report Share Posted April 23, 2008 OK . Good night guys . Believe me , the explanation is very easy. Now off to bed (1:00 AM local time).ZZZZZZ..... Quote Link to comment Share on other sites More sharing options...
0 Nikyma Posted April 23, 2008 Report Share Posted April 23, 2008 Reveal hidden contents 177, 10110001 Quote Link to comment Share on other sites More sharing options...
0 Guest Posted April 24, 2008 Report Share Posted April 24, 2008 akaslickster said: Reveal hidden contents 144 The number must be prime. Quote Link to comment Share on other sites More sharing options...
0 Guest Posted April 24, 2008 Report Share Posted April 24, 2008 Nikyma said: Reveal hidden contents 177, 10110001 He is not asking the next number, but the logic behind the sequence. Quote Link to comment Share on other sites More sharing options...
0 grey cells Posted April 24, 2008 Author Report Share Posted April 24, 2008 Nikyma said: Reveal hidden contents 177, 10110001 Sorry , It isn't 177 . And the sequence does not involve any binary calculation . Just plain binary numbers. Quote Link to comment Share on other sites More sharing options...
0 grey cells Posted April 24, 2008 Author Report Share Posted April 24, 2008 esjohnson said: He is not asking the next number, but the logic behind the sequence. Yes , you are right . But if someone comes at the right answer , then they must know the reasoning behind it. Quote Link to comment Share on other sites More sharing options...
0 grey cells Posted April 24, 2008 Author Report Share Posted April 24, 2008 Artificial I said: I did notice one thing, and I think I'm on the right track, but not all the way there yet. Reveal hidden contents If you list the numbers in order like this.... 2 5 11 17 137 149 173 but in binary, they make this... 00000010 00000101 00001011 00010001 10001001 10010101 10101101 From this you can notice that each line is only different from it's previous line by exactly 3 digits every time. I guess the pattern would then be to change 3 digits and still be prime. If this rule sticks, I think it means the next number would be 197. Reveal hidden contents am sorry that I didn't mention this in my previous posts . But I think it is almost a giveaway to the reasoning . But to be fair to you all ,I will give a hint . Now for the first 16 dec. numbers from 0 to 15 , the maximum number of bits used is 4 . So leave it at that. For the numbers after 15 , obviously the number of bits used are more than 4 . So for only these numbers , we have to use AI's representation . Sorry AI , I didn't say this beforehand . But as I have mentioned , this is a big hint. Quote Link to comment Share on other sites More sharing options...
Question
grey cells
Try solving this number sequence:
One I made myself with my fav ingredients.
Find the missing number:
2 , 5 , 11 , _ , 137 ,.....
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