Find the Next number in the pattern

[ecoli]

Each number, starting with one, has something done to it to get the next number...

 

What should the next number in the pattern be?

 

1, -1, 6, 29, 756, 570779,...

[Martin]

Each number' date=' starting with one, has something done to it to get the next number...

 

What should the next number in the pattern be?

 

1, -1, 6, 29, 756, 570779,...[/quote']

 

a guess

[hide]325,786,954,506[/hide]

[dan19_83]

i agree with the spoiler above but damn that was a tricky one!!

[ecoli]

no...That's not right, at least not according to what I'm doing...

 

Out of curiosity, what did you do to get your answer?

 

Here's a hint

 

[hide] it involves a fairly simple function [/hide]

 

Even bigger hint

 

[hide] that function is.... x^2-2x-1 [/hide]

[Martin]

Out of curiosity' date=' what did you do to get your answer?

 

 

[/quote']

 

[hide] I saw that the function that gets you from one to the next ALTERNATES between x^2-x-1 and x^2 - 3x +2

 

To get from 1 to -1, you go by x^2-x-1 (the function you propose would not work at least if used directly)

 

Then to get from -1 to 6, you go by x^2 - 3x +2

 

and then to get from 6 to 29 you go by x^2-x-1 again

 

and so on, you just keep alternating and it works and generates the sequence you wrote for us. [/hide]

 

BTW thanks for the puzzle, Coli, enjoyed working on it! Maybe you should explain your method if nobody comes up with the answer you had in mind in a day or so.

[ecoli]

Wow, Martin...you were a lot closer then I thought. Ok, well I see how your method would arrive with that answer. I did something else, a bit tricker then what you did.

 

I'll give it until friday, I think. Unless anybody gets really frustratesd...then I guess you can PM me.

[The Thing]

Is this thing recursive?

[ecoli]

I'm sorry, but I don't know what "recursive" means. Please explain!

[The Thing]

Does the function to calculate the next number involve the number(s) before the desired number?

[Martin]

Coli,

 

I am completely stumped.

[hide] how about another hint, or giving us the answer but blacked-out?[/hide]

[ecoli]

I sincerly apologize to everyone who was working on this thread, due to a simple math error on my part, the numbers in the pattern came out completely wrong. I am so sorry. I'm sure that's why no one was able to come up with the answer.

 

The pattern should have been 3, 5, 19, 341, 103380 ...

 

Please give me another chance!

[Martin]

The pattern should have been 3' date=' 5, 19, 341, 103380 ...

[/quote']

 

not to worry, a pattern with errors is just something more to puzzle over.

 

[hide] if it were 3, 5, 19, 341, 115939

then I would guess the rule was X^2 - X - 1

and I would say the next number is

13,441,735,781

 

but the 5th number in your patter is NOT the 115939 which I expected,

but is instead 103380

which stumps me. I do not see the pattern[/hide]