A Doubt

For how many values of $n>1$ there exist $n$ positive integers, $a_1, a_2,...,a_n$ satisfying: $(a_1)^2+(a_2)^2+...+(a_n)^2|(a_1+a_2+...+a_n)^2-1$

Easy Math Editor

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Math	Appears as
Remember to wrap math in `$` ... `$` or `\[` ... `\]` to ensure proper formatting.
`2 \times 3`	$2 \times 3$
`2^{34}`	$2^{34}$
`a_{i-1}`	$a_{i-1}$
`\frac{2}{3}`	$\frac{2}{3}$
`\sqrt{2}`	$\sqrt{2}$
`\sum_{i=1}^3`	$\sum_{i=1}^3$
`\sin \theta`	$\sin \theta$
`\boxed{123}`	$\boxed{123}$

Comments

$a_1=a_2-d=a_3-2d\cdots$ ?

A Former Brilliant Member - 10 months, 1 week ago

how?

Mohammed Imran - 10 months, 1 week ago

Arithmetic progression???

A Former Brilliant Member - 10 months, 1 week ago

nowrong

Mohammed Imran - 9 months, 2 weeks ago

Math	Appears as
Remember to wrap math in `\(` ... `\)` or `\[` ... `\]` to ensure proper formatting.
`2 \times 3`	$2 \times 3$
`2^{34}`	$2^{34}$
`a_{i-1}`	$a_{i-1}$
`\frac{2}{3}`	$\frac{2}{3}$
`\sqrt{2}`	$\sqrt{2}$
`\sum_{i=1}^3`	$\sum_{i=1}^3$
`\sin \theta`	$\sin \theta$
`\boxed{123}`	$\boxed{123}$