Write the first five terms of the following sequence and obtain the corresponding series :
$a_{1}=3, a_{n}=3 a_{n-1}+2$ for all $n\,>\,1$
$a_{1}=3, a_{n}=3 a_{n-1}+2$ for $n\,>\,1$
$\Rightarrow a_{2}=3 a_{1}+2=3(3)+2=11$
$a_{3}=3 a_{2}+2=3(11)+2=35$
$a_{4}=3 a_{3}+2=3(35)+2=107$
$a_{5}=3 a_{4}+2=3(107)+2=323$
Hence, the first five terms of the sequence are $3,11,35,107$ and $323$
The corresponding series is $3+11+35+107+323+\ldots$
Find the sum of integers from $1$ to $100$ that are divisible by $2$ or $5.$
Suppose $a_{1}, a_{2}, \ldots, a_{ n }, \ldots$ be an arithmetic progression of natural numbers. If the ratio of the sum of the first five terms of the sum of first nine terms of the progression is $5: 17$ and $110< a_{15} < 120$ , then the sum of the first ten terms of the progression is equal to -
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If $p,\;q,\;r$ are in $A.P.$ and are positive, the roots of the quadratic equation $p{x^2} + qx + r = 0$ are all real for