If `a_n = floor(n/2) + ceil(n/2)` is the `n`th term of the sequemce then what is `a_3`?

What is the 20^(th) term of the sequence defined by a_(n)=(n-1)(2-n)(3+n)?

What is the 15^(th) term of the sequence defined by: a_(n)=(n-1)(2-n)(3+n)?

19th term of the sequence a(n)=(n-2)/(n+3) is…………….

(i) The sum of the first n terms of an AP is ((5n^(2))/(2) + (3n)/(2)) . Find the nth term and the 20th term of this AP. (ii) The sum of the first n terms of an AP is ((3n^(2))/(2) + (5n)/(2)). Find its nth term and the 25th term.

Find the n^(th) term of the sequence 1/n^2, (1+n^2)/n^2, (1+2n^2)/n^2,...

Is it true to say that a_n= 3n^(2) + 5 is the n^(th) term of an A.P. sequence? Justify your answer.

If S_n = 5n^2 + 3n , then find its n^(th) term.

let a_1,a_2,a_3........be an arithmetic progression with comman difference 2. let S_n be the sum of first n terms of the sequence . if S_(3n)/s_n does not depend on n then the sim of the first 10 terms.