Question

How do you write the algebraic expression for "the sum on two consecutive number"?

Answer 1

`2 k + 1`, `(k in NN)`

Explanation:

Denoting some natural number by `k`, the next largest consecutive number may be denoted by `k + 1`.

Their sum will be `k + (k + 1) = 2 k + 1`

(where `k` is an element of the natural numbers, which are conventionally denoted by `NN`, as noted in parentheses in the brief summary answer above)