Thank you for using the timer - this advanced tool can estimate your performance and suggest more practice questions. We have subscribed you to Daily Prep Questions via email.
Customized for You
we will pick new questions that match your level based on your Timer History
Track Your Progress
every week, we’ll send you an estimated GMAT score based on your performance
Practice Pays
we will pick new questions that match your level based on your Timer History
Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.
Thank you for using the timer!
We noticed you are actually not timing your practice. Click the START button first next time you use the timer.
There are many benefits to timing your practice, including:
A certain computer program generates a sequence of numbers a1, a2, … ,
[#permalink]
Show Tags
Updated on: 23 Sep 2018, 23:19
1
7
00:00
A
B
C
D
E
Difficulty:
15% (low)
Question Stats:
79% (01:55) correct 21% (01:48) wrong based on 304 sessions
HideShow timer Statistics
A certain computer program generates a sequence of numbers a1, a2, … , an such that \(a_1 = a_2 = 1\) and \(a_k = a_{k-1} + 2a_{k-2}\) for all integers k such that 3 ≤ k ≤ n. If n > 6, then a7 = ?
Re: A certain computer program generates a sequence of numbers a1, a2, … ,
[#permalink]
Show Tags
03 Mar 2010, 10:53
12
1
Nihit wrote:
A certain computer program generates a sequence of numbers a1, a2, … , an such that a1 = a2 = 1 and ak = ak-1 + 2ak-2 for all integers k such that 3 ≤ k ≤ n. If n > 6, then a7 = ?
A. 32 B. 43 C. 64 D. 100 E. 128
Solving as mentioend earlier always helps but here's another approach for this particular problem a1 and a2 are odd and a3 would be odd and all the numbers in the sequence are odd as they are of the format odd number + 2 * odd number. a7 is odd and only B has an odd number
Re: A certain computer program generates a sequence of numbers a1, a2, … ,
[#permalink]
Show Tags
13 Sep 2008, 08:36
2
Nihit wrote:
A certain computer program generates a sequence of numbers a1, a2, … , an such that a1 = a2 = 1 and ak = ak-1 + 2ak-2 for all integers k such that 3 ≤ k ≤ n. If n > 6, then a7 = ?
Re: A certain computer program generates a sequence of numbers a1, a2, … ,
[#permalink]
Show Tags
01 Mar 2010, 06:10
x2suresh wrote:
Nihit wrote:
A certain computer program generates a sequence of numbers a1, a2, … , an such that a1 = a2 = 1 and ak = ak-1 + 2ak-2 for all integers k such that 3 ≤ k ≤ n. If n > 6, then a7 = ?
Re: A certain computer program generates a sequence of numbers a1, a2, … ,
[#permalink]
Show Tags
03 Mar 2010, 09:12
Nihit wrote:
A certain computer program generates a sequence of numbers a1, a2, … , an such that a1 = a2 = 1 and ak = ak-1 + 2ak-2 for all integers k such that 3 ≤ k ≤ n. If n > 6, then a7 = ?
Re: A certain computer program generates a sequence of numbers a1, a2, … ,
[#permalink]
Show Tags
29 Jun 2011, 16:08
even though this is good observation. this approach wont work if there are more than 1 odd number in the answer choices.
chix475ntu wrote:
Nihit wrote:
A certain computer program generates a sequence of numbers a1, a2, … , an such that a1 = a2 = 1 and ak = ak-1 + 2ak-2 for all integers k such that 3 ≤ k ≤ n. If n > 6, then a7 = ?
A. 32 B. 43 C. 64 D. 100 E. 128
Solving as mentioend earlier always helps but here's another approach for this particular problem a1 and a2 are odd and a3 would be odd and all the numbers in the sequence are odd as they are of the format odd number + 2 * odd number. a7 is odd and only B has an odd number
Re: A certain computer program generates a sequence of numbers a1, a2, … ,
[#permalink]
Show Tags
17 Feb 2014, 12:24
x2suresh wrote:
Nihit wrote:
A certain computer program generates a sequence of numbers a1, a2, … , an such that a1 = a2 = 1 and ak = ak-1 + 2ak-2 for all integers k such that 3 ≤ k ≤ n. If n > 6, then a7 = ?
Re: A certain computer program generates a sequence of numbers a1, a2, … ,
[#permalink]
Show Tags
17 Feb 2014, 20:29
1
jlgdr wrote:
x2suresh wrote:
Nihit wrote:
A certain computer program generates a sequence of numbers a1, a2, … , an such that a1 = a2 = 1 and ak = ak-1 + 2ak-2 for all integers k such that 3 ≤ k ≤ n. If n > 6, then a7 = ?
Why do they give you this stuff? '3 ≤ k ≤ n. If n > 6'?
Thanks Cheers J
Because the relation they gave you \(a_k = a_{k-1} + 2a_{k-2}\) holds only from the third term onwards till the last term \(a_n\). That is, k should be 3 or more and will take the last value of n. This relation doesn't hold for the first and second terms and holds for all the rest of the terms. That is what this 'stuff' specifies.
If n > 6 tells you that the sequence has more than 6 terms i.e. at least 7 terms.
_________________
Karishma Veritas Prep GMAT Instructor
Learn more about how Veritas Prep can help you achieve a great GMAT score by checking out their GMAT Prep Options >
GMAT self-study has never been more personalized or more fun. Try ORION Free!
Re: A certain computer program generates a sequence of numbers a1, a2, … ,
[#permalink]
Show Tags
11 Mar 2015, 07:13
Nihit wrote:
A certain computer program generates a sequence of numbers a1, a2, … , an such that a1 = a2 = 1 and ak = ak-1 + 2ak-2 for all integers k such that 3 ≤ k ≤ n. If n > 6, then a7 = ?
A. 32 B. 43 C. 64 D. 100 E. 128
Hi,
It will help if (k-1) and (k-2) are written as subscript. Initially, I understood it to be (ak-1+2ak-2) which, without sub-scripting equals ak + 2ak - 3.
Re: A certain computer program generates a sequence of numbers a1, a2, … ,
[#permalink]
Show Tags
03 Nov 2018, 05:57
Hello from the GMAT Club BumpBot!
Thanks to another GMAT Club member, I have just discovered this valuable topic, yet it had no discussion for over a year. I am now bumping it up - doing my job. I think you may find it valuable (esp those replies with Kudos).
Want to see all other topics I dig out? Follow me (click follow button on profile). You will receive a summary of all topics I bump in your profile area as well as via email.
_________________
close
79% (01:55) correct 
