Solve the Puzzle: 4, 5, 14, 185, .... - Ray Salmon

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Discussion Overview

The discussion revolves around a numerical sequence presented as a puzzle: 4, 5, 14, 185, ... Participants explore potential patterns, mathematical relationships, and methods for generating the next number in the series.

Discussion Character

  • Exploratory
  • Mathematical reasoning
  • Debate/contested

Main Points Raised

  • One participant notes the differences between the numbers (1, 9, 171) and explores factors of 171, suggesting a relationship involving powers of 9.
  • Another participant introduces a polynomial function that fits the given numbers, stating that the next number could be arbitrary, with examples of different polynomial fits yielding different results for f(5).
  • Concerns are raised about the nature of the problem, questioning whether it is intended to be solved by finding a generating equation or if any number could be chosen as the next term.
  • A later contribution identifies a pattern where each number is 11 less than a perfect square, proposing that the next number could be calculated as 185² - 11 = 34,214.

Areas of Agreement / Disagreement

Participants express differing views on the nature of the sequence and the validity of various approaches to find the next number. There is no consensus on a single method or solution, and multiple competing ideas remain unresolved.

Contextual Notes

Some participants highlight the arbitrary nature of the next number in the sequence, depending on the chosen method of fitting or generating the series. The discussion also reflects uncertainty regarding the assumptions behind the puzzle's intent.

karush
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ok somebody sent me this on youtube but I don't think is a workable series

Rimbus Jift
@ray salmon Quick IQ test... Solve: 4, 5, 14, 185, ...

so first the difference between the numbers is 1,9,171so far just some ideas
The factors of 171 are 1, 3, 9, 19, 57, 171
$9^0 =1$ and $4+1=5$
$9^1 =9$ and $5+9=14$

$9+5=14$
$9+14=19$
$9\cdot 19=171 $
anyway ?

i plugged into W|F but didn't return a series
 
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karush said:
ok somebody sent me this on youtube but I don't think is a workable series

Rimbus Jift
@ray salmon Quick IQ test... Solve: 4, 5, 14, 185, ...

so first the difference between the numbers is 1,9,171so far just some ideas
The factors of 171 are 1, 3, 9, 19, 57, 171
$9^0 =1$ and $4+1=5$
$9^1 =9$ and $5+9=14$

$9+5=14$
$9+14=19$
$9\cdot 19=171 $
anyway ?

i plugged into W|F but didn't return a series
You should know by now that you can choose any number to be the next one. For example we can use
[math]f(x) = -28 x^4 + \dfrac{917}{3} x^3 - 1130 x^2 + \dfrac{5014}{3} x - 815[/math]

and get f(1) = 4, f(2) = 5, f(3) = 14, f(4) = 185. and the next number in the series will be f(5) = 0.

-Dan
 
ok actually I haven't seen that,
the few series I worked on just plug and played with values of n till you got an eq to generate the series
the imperative "solve" does not insist that it is series generated by an eq but I assume that was the intention
why woufd f(5)=0 or is that just arbitrary

Anyway it does seem slam dung stuff
 
karush said:
ok actually I haven't seen that,
the few series I worked on just plug and played with values of n till you got an eq to generate the series
the imperative "solve" does not insist that it is series generated by an eq but I assume that was the intention
why woufd f(5)=0 or is that just arbitrary

Anyway it does seem slam dung stuff
f(5) is arbitrary. For example:
[math]f(x) = -\dfrac{671}{24} x^4 + \dfrac{1221}{4} x^3 - \dfrac{27085}{24} x^2 + \dfrac{6677}{4} x -814[/math]

gives f(1) = 4, f(2) = 5, f(3) = 14, f(4) = 185, and f(5) = 1.

etc. And you can do other fits aside from polynomials pretty much so long as you have 5 unknowns and the system can be solved. (Polynomials are easy to fit which I why I prefer to use them for demonstrations.)

A problem like this assumes that you can figure out a pattern but unfortunately any more information that you might get could change that answer. So I feel that problems like this are just silly.

-Dan
 
ok I think so too ,...

but curious
what online series calculators are good if you just give a list of 6 numbers which assumes a generator eq
I guess W|F will but haven't tried
 
Someone just posted this on YT again in a random Covid video (9/10/23). I started down the same line as above, noticing the differences of each number in the series is a multiple of 3, but this didn't lead anywhere. I played with the numbers and realized they are each 11 away from a square.

In fact 4²-11 = 5; 5²-11 = 14; 14²-11=185. So the answer is 185²-11 = 34,214.
 
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