Form a function

Form a function which represents the following series

$\large \color{#D61F06}1,\color{#3D99F6}-1,-1,\color{#D61F06}1,1,1,\color{#3D99F6}-1,-1,-1,-1, \color{#333333} \cdots$

That is, putting 1 in function should give 1 , putting 2 and 3 should give -1 and so on.

#NumberTheory

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`italics` or `_italics_`	italics
`bold` or `__bold__`	bold
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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

@Mark Hennings , @Chew-Seong Cheong , @Anirudh Sreekumar

Vilakshan Gupta - 3 years, 5 months ago

$f(x)=(-1)^{n+1} : \dfrac{n(n-1)}{2}<x\leq\dfrac{n(n+1)}{2};x,n\in\mathbb{N}$

Anirudh Sreekumar - 3 years, 5 months 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}`	$\boxed{123}$