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Souvik Dey

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Top Questions

If $f:\mathbb{R}\to\mathbb{R}$ is continuous and $f(x)\neq x$ for all $x$, must it be true that $f(f(x))\neq x$ for all $x$?

real-analysis general-topology continuity functional-equations asked Apr 23 at 8:06

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$f(x+y) + f( f(x) + f(y) ) = f( f( x+f(y) ) + f( y+f(x) ) )$

functional-equations asked Oct 17 '12 at 10:00

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Question about an upper bound

number-theory inequality asked Oct 12 '12 at 6:55

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$\frac{a+b}{b+c} + \frac{c+d}{d+a} ≤ 4(\frac{a+c}{b+d}) ; a , b , c , d ∈ [1 , 2]$

inequality asked Oct 18 '12 at 4:29

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The Diophantine equation, $x^2 - y^2 = z^3$

number-theory asked Sep 21 '12 at 9:28

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To estimate $\sum_{m=1}^n \Big(d\big(m^2\big)\Big)^2$

number-theory analytic-number-theory asked Apr 24 at 5:47

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$f: \Bbb N→ \Bbb N$ , $f\big(f(m) +f(n)\big)=m+n$ $\space$ for all $m,n∈\Bbb N$

functions functional-equations asked Apr 25 at 6:31

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Top Answers

$f(x+y) + f( f(x) + f(y) ) = f( f( x+f(y) ) + f( y+f(x) ) )$

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Primes and Twine primes and their sums.

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