MathDB

Let

A_n

be the set of real numbers such that each element of

A_n

can be expressed as

1+\frac{a_1}{\sqrt{2}}+\frac{a_2}{(\sqrt{2})^2}+\cdots +\frac{a_n}{(\sqrt{n})^n}

for given

n.

Find both

|A_n|

and sum of the products of two distinct elements of

A_n

where each

a_i

is either

1

-1.

Problem Statement