Clarification

Hey can anyone just clarify this (i+j)/2 in this question: A subset S of {1,2,…,n} is said to be packed if whenever i,j∈S the number ⌊(i+j)/2⌋ is also in S. Determine how many subsets of {1,2,…,25} are packed. This is greatest integer function right?

Easy Math Editor

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`2 \times 3`	$2 \times 3$
`2^{34}`	$2^{34}$
`a_{i-1}`	$a_{i-1}$
`\frac{2}{3}`	$\frac{2}{3}$
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Comments

It is greatest integer got it. So,clarified. Sorry, for the trouble you got by reading this.;)

HArshil PAtel - 7 years, 11 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}`	$\boxed{123}$