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visits member for 4 years, 5 months
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Jan
3
reviewed Reject Prove that there are no such different positive numbers that satisfy both $a+b=c+d$ and $a^3+b^3=c^3+d^3$.
Jan
3
reviewed Close About Saturation of Monomial Ideals
Jan
3
comment Show $\binom{n}{k}\binom{k}{a} = \binom{n}{a}\binom{n-a}{k-a}$ by block-walking interpretation of Pascal's triangle
Related: math.stackexchange.com/q/534202
Jan
3
reviewed Close The zero point problem of a function .
Jan
3
comment Is there anything to be learned from the spectrum of a cohomology ring?
AFAIK this POV is more useful in equivariant cohomology. For example, in the context of localization theorems it's natural (at least) to view $H_G(X)$ as a sheaf over $\operatorname{Spec}H_G(pt)$. See also Quillen. The Spectrum of an Equivariant Cohomology Ring and Goresky, MacPherson. On the Spectrum of the Equivariant Cohomology Ring...
Jan
3
comment Loop space and $K$-theory
possible duplicate of Yoneda's lemma and $K$-theory.
Jan
3
reviewed Close Why is $-a \times -b = ab$?
Jan
3
revised what does the “L” in “L-function” stand for?
ref. to the answer
Jan
3
reviewed Leave Open Prime factor of $2 \uparrow \uparrow 4 + 3\uparrow \uparrow 4$
Jan
3
revised If $x=123456789101112131415161718$, then $x\equiv 6\pmod{16}$ and $x\equiv 0\pmod 6$
edited tags; edited title
Jan
3
reviewed Close Prove $S_g$ retracts to $C$
Jan
2
reviewed Leave Open Solve $\frac{b}{a}=a.b$ in decimal
Jan
2
reviewed Close Famous Problem of Euler
Jan
2
reviewed Close Matrices and vectors calculating angle.
Jan
2
comment Understanding the relationship between $Sp(n)$ and $Sp(2n,\mathbb{C})$
Have you tried Wikipedia?
Jan
2
comment Explicit formula for Fermat's 4k+1 theorem
Shouldn’t this ‘Weyl’ be ‘Weil’?
Jan
2
answered Explicit formula for Fermat's 4k+1 theorem
Jan
2
revised Strehl identity for the sum of cubes of binomial coefficients
added 320 characters in body
Jan
2
reviewed Close Maths without irrational numbers
Jan
2
reviewed No Action Needed Limit Points Explanation required