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S.C.

Chennai, India

http://google.co.in

Graduate student in Mathematics.

--

Reductio ad absurdum, which Euclid loved so much, is one of a mathematician's finest weapons. It is a far finer gambit than any chess play: a chess player may offer the sacrifice of a pawn or even a piece, but a mathematician offers the game. - G.H. Hardy

A Mathematician's Apology (London 1941).

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Top Questions
235 votes

If $f$ is infinitely differentiable then $f$ coincides with a polynomial

real-analysis polynomials asked Jul 31, 2010 at 21:37
mathoverflow.net

94 votes

Recovering accidentally deleted files

backup rm data-recovery asked Oct 3, 2010 at 19:46
unix.stackexchange.com

51 votes

Function satisfying $f^{-1} =f'$

real-analysis differential-equations functional-equations asked Jul 31, 2010 at 19:57
mathoverflow.net

22 votes

How to show $\sum_{k=0}^{n}\binom{n+k}{k}\frac{1}{2^k}=2^{n}$

combinatorics binomial-coefficients generating-functions combinatorial-proofs asked Jul 29, 2016 at 11:22
math.stackexchange.com

20 votes

On a Conjecture of Schinzel and Sierpinski

nt.number-theory analytic-number-theory asked Jan 29, 2011 at 19:48
mathoverflow.net

19 votes

Ramanujan's eccentric Integral formula

ca.analysis-and-odes cv.complex-variables sequences-and-series asked Jun 3, 2011 at 10:33
mathoverflow.net

16 votes

A few words in a coloured/grey background box

color boxes highlighting asked Jan 1, 2013 at 15:54
tex.stackexchange.com

15 votes

Example of a group which has $\text{SL}_{n}(\mathbb{Z})$ as the automorphism group

gr.group-theory automorphism-groups asked Sep 10, 2011 at 13:58
mathoverflow.net

15 votes

How does one evaluate $\int \frac{\sin(x)}{\sin(5x)} \ dx$

calculus integration indefinite-integrals trigonometric-integrals asked Oct 19, 2014 at 15:01
math.stackexchange.com

14 votes

Ramanujan's Incorrect formula

ca.analysis-and-odes sequences-and-series asked May 28, 2011 at 17:30
mathoverflow.net

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Top Answers
53
Not especially famous, long-open problems which anyone can understand
mathoverflow.net

49
Not especially famous, long-open problems which anyone can understand
mathoverflow.net

47
Counterexamples in algebra?
mathoverflow.net

35
Not especially famous, long-open problems which anyone can understand
mathoverflow.net

28
A good book of functional analysis
mathoverflow.net

20
Can the group $\mathbb Z \times \mathbb Z$ be written as union of finitely many proper subgroups of it?
math.stackexchange.com

17
Prove: $\sin (\tan x) \geq {x}$
math.stackexchange.com

14
Fundamental problems whose solution seems completely out of reach
mathoverflow.net

14
How can I show that $\begin{pmatrix} 1 & 1 \\ 0 & 1\end{pmatrix}^n = \begin{pmatrix} 1 & n \\ 0 & 1\end{pmatrix}$?
math.stackexchange.com

14
Find the value of: $\sum_{n=1}^{50}n(n!)$
math.stackexchange.com

13
Fundamental problems whose solution seems completely out of reach
mathoverflow.net

12
Fundamental problems whose solution seems completely out of reach
mathoverflow.net

12
Not especially famous, long-open problems which anyone can understand
mathoverflow.net

11
Is $\left( {{2}^{x}}-1 \right)\left( {{5}^{x}}-1 \right)$ a square number for integer $x>1$
math.stackexchange.com

10
Request for the proof of a result from Ramanujan's letter to Hardy.
mathoverflow.net

10
Old books still used
mathoverflow.net

9
List of open problems of formal languages
mathoverflow.net

9
Alternating sum of binomial coefficients multiplied by (1/k+1)
math.stackexchange.com

9
How to calculate $\lim_{x\to0} \frac{\ln(1+x)+\ln(1-x)}{x^2}$?
math.stackexchange.com

9
Sum of $50$ terms of $\cot^{-1}3+\cot^{-1}7+\cot^{-1}13+\cot^{-1}21+.....$
math.stackexchange.com

8
What's the "best" proof of quadratic reciprocity?
mathoverflow.net

7
What are your favorite instructional counterexamples?
mathoverflow.net

7
Transforming a Riemann Sum to an integral.
math.stackexchange.com

7
Tricky integration/functions problem
math.stackexchange.com

6
Transliteration of sanskrit or devanagari texts using polyglossia or other packages
tex.stackexchange.com

6
Examples of interesting false proofs
mathoverflow.net

6
How to evaluate the limit $\lim_{x\to 0} ((1+2x)^{1/3 }-1)/ x$ without using the l'Hospital's rule?
math.stackexchange.com

6
What is the limit of $\lim_{n\to \infty}\frac{1-2+3-4+\cdots+(-2n)}{\sqrt{n^2+1}}$?
math.stackexchange.com

6
Contest problems with connections to deeper mathematics
mathoverflow.net

6
Proving a congruence using Wilson Theorem
math.stackexchange.com

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