Let $X$ be the set consisting of the first $2018$ terms of the arithmetic progression $1,6,11$,
. . . .and $Y$ be set consisting of the first $2018$ terms of the arithmetic progression $9, 16, 23$,. . . . . Then, the number of elements in the set $X \cup Y$ is. . . .
$3747$
$3748$
$3749$
$3750$
The sum of first $n$ natural numbers is
If $\log _{3} 2, \log _{3}\left(2^{x}-5\right), \log _{3}\left(2^{x}-\frac{7}{2}\right)$ are in an arithmetic progression, then the value of $x$ is equal to $.....$
If the sum of the first $n$ terms of a series be $5{n^2} + 2n$, then its second term is
Write the first five terms of the sequences whose $n^{t h}$ term is $a_{n}=n(n+2)$
If ${A_1},\,{A_2}$ be two arithmetic means between $\frac{1}{3}$ and $\frac{1}{{24}}$ , then their values are