Next Number | 5 Sep 2009
 

Which is the next number in below series.

1, 2, 7, 12, 19, 42, ?

Re: Next Number | 5 Sep 2009
 

Looks like we would have OP as winner. :D

Re: Next Number | 5 Sep 2009
 

Nothing found here:
http://www.research.att.com/~njas/se...lish&go=Search

Without commas this returns 432 pages of results; looked through the first few but there was nothing obvious.

So we need more terms to deduce the sequence.

Of course, any number can be the answer, for example 99, because these are the roots of the equation
x^7-182*x^6+10500*x^5-252586*x^4+2762303*x^3-13306896*x^2+24059196*x-13272336

Re: Next Number | 5 Sep 2009
 

Even I searched there, in vain :(

Yeah, but then how do we express the general term, say 'n'th term of the series ?? :undecided
As you already said, we probably need some more terms ... :thinking:

Re: Next Number | 5 Sep 2009
 

Kshiteej can we have the answer of this so we can have the question for today.

Re: Next Number | 5 Sep 2009
 

Assuming that is enough to deduce the series, then using the same technique as before I get 113.

Re: Next Number | 5 Sep 2009
 

that was nice xpi0t0s

Re: Next Number | 5 Sep 2009
 

The next number is 37. Am i right?

Re: Next Number | 5 Sep 2009
 

Hi all,
sorry for my late reply.
Consider alternative terms set 2 ie 2,12,42
12-2 = 10 = (2)^3 + 2
42-12 = 30 = (3)^3 + 3

Consider alternative terms set 1 ie. 1,7,19
7-1 = 6 = (2)^2 + 2
19-7= 12 = (3)^2 + 3

as the next number belongs to alternative set 1 ( because next numbers postion is odd)

next number should be 19 + (4)^2 + 4 = 39


So the answer is 39.

Re: Next Number | 5 Sep 2009
 

I too thought in the same angle. But some thing went wrong

1, 2, 7, 12, 19, 42

The diff b/w 1st and third is 6 (7-1)

The diff b/w 5th and 3rd is 12 (19-7)

So,The diff b/w 7th and 5th should be 18 (37-19) which follows multiples of 6.

Similarly,
the diff b/w 4th and 2nd is 10 (12-2)

the diff b/w 6th and 4th is 30 (42-12)