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2d
revised Is at least one of $6k + 1$ or $6k-1$ prime?
edited tags
Jul
18
revised if ∑_(n=1)^∞an is absolutely convergent then which of the following is not true?
edited tags
Jul
18
revised Eilenberg-Maclane space $K(G\rtimes H, 1)$ for a semi-direct product.
edited tags
Jul
17
revised What does the colon use in the decimal place mean?
edited tags
Jul
15
revised How to find the length of diagonal of a rhombus
rolled back to a previous revision
Jul
14
revised if each each of two natural numbers a and b is a sum of two squares then ab is also a sum of two squares
more descriptive title
Jul
10
revised How many divisors are there in 2015, that is d(2015)?
edited tags
Jun
15
revised Gauss-type sums for cube roots
One concrete positive result added (+a typo fixed)
Jun
2
revised CHECK: Let p be a prime number. Show that $\binom{2p}{p}$ is congruent to $2$ mod $p$.
edited tags
May
26
revised Spin manifold and the second Stiefel-Whitney class
texified
May
23
revised Let $a,m,n \in \mathbf{N}$. Show that if $\gcd(m,n)=1$, then $\gcd(a,mn)=\gcd(a,m)\cdot\gcd(a,n)$.
edited tags
May
23
revised Find all integers $n$ (positive, negative, and zero) so that $n^2 + 1$ is divisible by $n + 1$.
edited tags
May
21
revised Direct proof that for a prime $p$ if $p\equiv 1 \bmod 4$ then $l(\sqrt{p})$ is odd.
edited tags
May
21
revised Open covers by simply connected sets and fundamental group
more descriptive title
May
20
revised Fibonacci combinatorial identity
edited tags
May
20
revised Finding integral solutions to the equation $x^4-ax^3-bx^2-cx-d=0$
edited title
May
19
revised notation used in algebraic topology
edited tags
May
18
revised Proof that the subalgebra generated by any two elements of $\mathbb{O}$ is isomorphic to $\mathbb{R}$, $\mathbb{C}$, or $\mathbb{H}$
edited tags
May
18
revised Unit or non-zero octonions form an $A_\infty$-space?
added 180 characters in body
May
18
revised Quaternionic veronese Embedding
link fixed