Try this TOMATO problem from I.S.I. B.Stat Entrance Objective Problem based on Combination of Sequence.
The two sequence of numbers {1,4,16,64,.....} and {3,12,48,192,.....} are mixed as follows {1,3,4,12,16,48,64,192,....}. One of the numbers in the mixed series is 1048576. Then the number immediately preceeding it is
Logic
Sequence
Integers
Answer: 786432.
B.Stat Objective Question 79
Challenges and Thrills of Pre-College Mathematics by University Press
The first series is of form \(4^{r}\) for \(r \geq 0\) \(r \in\) set of natural numbers the second series is of form \(3 \times 4^{r}\) for \(r \geq 0\) \(r \in\) set of natural numbers and the third series is of \(4^{r}\),\(3 \times 4^{r}\) in alternate element form for \(r \geq 0\) \(r \in\) set of natural numbers
given that 1048576=\(4^{r}\)=\(4^{10}\)
then preceeding term \(3 \times 4^{9}\)=(3)(262144)=786432.
I.S.I. & C.M.I. Entrance Program
Taught by students and alumni of I.S.I. & C.M.I.
