Arithmetic Sequence
We can observe that we are adding 5 each time to the numbers, meaning this is an arithmetic sequence with a common difference d=5
Explicit Relation
We can establish the relation,
u(n)=u⁰+nd
where u(n) is the nth term (any term).
u⁰ is out first term (2)
d is the common difference (5)
u(n)=u⁰+nd
92 =2 +5n
5n =90
n =18
This sequence admits 19 terms since we start counting from 0 till 18.
Summation
S= number of terms/2 ×(u¹⁸+u⁰)
That's ur answer :)