+King of Herdaz Posted December 20, 2019 Report Share Posted December 20, 2019 (edited) I came up with this sequence in math class a couple of months ago when we were asked to make up a rule, write down a sequence using that rule, and pass them around the room. When you figured out the rule you were supposed to trade with someone else and try to figure out that one. Afterwards the professor put the sequences that stumped people on the board and we figured them out together. However the following sequence which I made wasn't solved and stumped the whole class, professor included. So here it is: 0,0,3,16,45,120,280,624,1323,2720... Try to figure the rule for this sequence. Edited June 15, 2020 by King of Herdaz 1 Quote Link to comment Share on other sites More sharing options...
GoWibble Posted December 20, 2019 Report Share Posted December 20, 2019 Just saying, this is nearly impossible. Here is another one! 1, 1, 2, 6, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0... GL! Can we limit it down to simple functions, or not? (for the first one) 0 Quote Link to comment Share on other sites More sharing options...
+King of Herdaz Posted December 20, 2019 Author Report Share Posted December 20, 2019 (edited) If you want a hint: Spoiler it is two sequences multiplied together. the first term in both sequences is 0 Edited December 20, 2019 by King of Herdaz 0 Quote Link to comment Share on other sites More sharing options...
+King of Herdaz Posted December 20, 2019 Author Report Share Posted December 20, 2019 41 minutes ago, GoWibble said: Just saying, this is nearly impossible. Here is another one! 1, 1, 2, 6, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0... GL! Can we limit it down to simple functions, or not? (for the first one) Does it ever change from zero after the first 4 terms?? 0 Quote Link to comment Share on other sites More sharing options...
GoWibble Posted December 20, 2019 Report Share Posted December 20, 2019 (edited) nope though I didn't go to infinity... oh, and the first one is the 0th one and your magic number is 2 Edited December 20, 2019 by GoWibble 0 Quote Link to comment Share on other sites More sharing options...
+King of Herdaz Posted December 20, 2019 Author Report Share Posted December 20, 2019 36 minutes ago, GoWibble said: and your magic number is 2 What do you mean? 0 Quote Link to comment Share on other sites More sharing options...
GoWibble Posted December 20, 2019 Report Share Posted December 20, 2019 It has a 2 in the equation. 0 Quote Link to comment Share on other sites More sharing options...
Ixthos Posted December 20, 2019 Report Share Posted December 20, 2019 @King of Herdaz is the answer Spoiler The Fibonacci sequence multiplied by the multiple of successive integers separated by two? So 0, 1, 1, 2, 3, 5, 8, 13, 21, 34 (0, 1, (0+1 = 1), (1+1 = 2), (1+2 = 3), (2+3 = 5), ... N(m-2)+N(m-1) = N(m)) 0, 0, 3, 8, 15, 24, 35, 48, 63, 80 (0, 0, (1*3), (2*4), (3*5), (4*6), ... N(y)*N(y+2) = N(z)) Can you answer this one? 2, 72, 5184, 640000, 121500000, 32934190464, 12089663946752, ... 1 Quote Link to comment Share on other sites More sharing options...
+King of Herdaz Posted December 22, 2019 Author Report Share Posted December 22, 2019 On 12/20/2019 at 2:21 PM, Ixthos said: @King of Herdaz is the answer Hide contents The Fibonacci sequence multiplied by the multiple of successive integers separated by two? So 0, 1, 1, 2, 3, 5, 8, 13, 21, 34 (0, 1, (0+1 = 1), (1+1 = 2), (1+2 = 3), (2+3 = 5), ... N(m-2)+N(m-1) = N(m)) 0, 0, 3, 8, 15, 24, 35, 48, 63, 80 (0, 0, (1*3), (2*4), (3*5), (4*6), ... N(y)*N(y+2) = N(z)) Spoiler you got the first part right, and while i used (n^2)-1, what you gave for the second part also works. good job! 1 Quote Link to comment Share on other sites More sharing options...
Ixthos Posted December 23, 2019 Report Share Posted December 23, 2019 On 12/22/2019 at 2:56 AM, King of Herdaz said: Hide contents you got the first part right, and while i used (n^2)-1, what you gave for the second part also works. good job! Spoiler Makes sense. (n-1)(n+1) = n^2 - n + n - 1 = n^2 - 1 :-) 1 Quote Link to comment Share on other sites More sharing options...
Ammonakin Posted January 22, 2020 Report Share Posted January 22, 2020 (edited) On 12/20/2019 at 11:21 AM, Ixthos said: @King of Herdaz is the answer Reveal hidden contents The Fibonacci sequence multiplied by the multiple of successive integers separated by two? So 0, 1, 1, 2, 3, 5, 8, 13, 21, 34 (0, 1, (0+1 = 1), (1+1 = 2), (1+2 = 3), (2+3 = 5), ... N(m-2)+N(m-1) = N(m)) 0, 0, 3, 8, 15, 24, 35, 48, 63, 80 (0, 0, (1*3), (2*4), (3*5), (4*6), ... N(y)*N(y+2) = N(z)) Can you answer this one? 2, 72, 5184, 640000, 121500000, 32934190464, 12089663946752, ... Yeah. ...The OEIS is a very powerful tool Edited January 22, 2020 by Ammon Kunzler 1 Quote Link to comment Share on other sites More sharing options...
Ixthos Posted January 23, 2020 Report Share Posted January 23, 2020 8 hours ago, Ammon Kunzler said: Yeah. ...The OEIS is a very powerful tool Cheater :-P :-D 1 Quote Link to comment Share on other sites More sharing options...
Ammonakin Posted January 26, 2020 Report Share Posted January 26, 2020 Heres another 0,1,8,3,20,45,12,42,40,27,50,88,108,91,126,45,32,51,144,76,120... Quick warning: it is pretty irrational and counter-intuitive, though not too complicated. 1 Quote Link to comment Share on other sites More sharing options...
Ixthos Posted January 28, 2020 Report Share Posted January 28, 2020 (edited) @Ammonakin Spoiler Hmmm ... so far, just looking at it, I see that the zeroth entry is zero, the first is 1*1, the second is 2*4, the third is 3*1, the fifth is 5*4, the sixth is 6*2, the seventh is 7*6, the eighth is 8*5, the ninth is 9*3, the tenth is 10*5, the eleventh is 11*8, ... and so making a list of the number unlike its place, we get the sequence of 1, 4, 1, 5, 9, ... which makes me wonder if the first number - the multiple for zero - was a three. Fancy some pi? ;-) Edited January 28, 2020 by Ixthos Forgot to put this in spoilers! 1 Quote Link to comment Share on other sites More sharing options...
Adolinalsium Posted June 15, 2020 Report Share Posted June 15, 2020 I can't solve the first one lol 0 Quote Link to comment Share on other sites More sharing options...
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.