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visits member for 4 years, 5 months
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9h
answered What motiveted Gauss to formulate his theorem on quadratic reprocity?
Dec
13
asked Law of sines: uniform proof of Euclidean, spherical & hyperbolic cases
Jul
11
answered Recurrence $(n+2)\text{Cat}_{n+1}=(4n+2)\text{Cat}_n$ for non-crossing matchings
Jun
10
answered Example of something easier to count with $q$-analog?
May
26
answered Spin manifold and the second Stiefel-Whitney class
May
20
answered Fibonacci combinatorial identity
May
20
answered Asking About Binomial Sum Related to Fibonacci
May
15
answered Unit or non-zero octonions form an $A_\infty$-space?
May
13
answered Trigonometric identity involving sum of “Dirichlet kernel like” fractions
May
3
answered Computing $H^\bullet(\Bbb Z/n\Bbb Z)$
May
3
answered When characteristic classes determine a bundle?
Apr
30
answered Converse of a fixed-point theorem
Apr
23
answered Is there a “natural” / “categorical” definition of the “parity” of a permutation?
Apr
18
answered Topological invariance of chern classes
Apr
18
answered Homology Whitehead theorem for non simply connected spaces
Feb
2
answered How prove this $\sum_{k=0}^n \binom{n}{k} \binom{(p-1)n}{k} \binom{pn+k}{k} = \binom{pn}{n}^2 $
Jan
19
wiki created cohomological-operations excerpt
Jan
19
asked Ramanujan-type trigonometric identities with cube roots, generalizing $\sqrt[3]{\cos(2\pi/7)}+\sqrt[3]{\cos(4\pi/7)}+\sqrt[3]{\cos(8\pi/7)}$
Jan
19
answered Number of matrices with weakly increasing rows and columns
Jan
18
wiki created topological-k-theory excerpt