bio  website  perso.enslyon.fr/… 

location  Lyon  
age  36  
visits  member for  5 years, 1 month 
seen  yesterday  
stats  profile views  2,599 
I am a number theorist working at the École normale supérieure de Lyon in France. My research interests are elliptic curves, Lfunctions and zeta functions, especially the study of their special values (conjectures by Beilinson, Bloch, Kato, Zagier...).
1d

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Is it possible to evaluate Connect 4 positions with Combinatorial Game Theory?
If I recall correctly, Connect 4 is a first player win. 
1d

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Is it possible to evaluate Connect 4 positions with Combinatorial Game Theory?
Just for the record, Connect 4 has already been solved around 1988 tromp.github.io/c4/c4.html 
Jun 27 
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Computing an eigencuspform in $S_2(\Gamma_0(1776))$
The natural way to embed abelian varieties into projective space is to use theta functions. Then, finding equations amounts to find algebraic relations between them. The first theta relations were found by Riemann, they are quadratic. Moreover, by results of Mumford and Kempf, if the line bundle is ample enough then Riemann's relations generate all the relations. For an abelian 3fold, the best you can hope for is embedd into $\mathbf{P}^7$, but if you want quadratic equations you probably need higher dimensional projective space. See Chap. 7 in BirkenhakeLange "Complex abelian varieties". 
Jun 26 
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Computing an eigencuspform in $S_2(\Gamma_0(1776))$
For your second question, as you probably know there is no such thing as Cremona's tables for abelian varieties. On the other hand, you can try to compute the complex periods of $A_f$ (using modular symbols). At least they determine $A_f$ as an abelian variety over C, but then it depends on what you want to do. 
Jun 19 
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different definitions of epsilon constants for representations of GL(2) from modular forms
You can also look at Gealy's thesis thesis.library.caltech.edu/5020 where he recalls the normalization for the global Lfunction and epsilonfactor of a modular form (see Section 5.4 but also Chapter 8 for the finite epsilon factors). In any case, I think it's reasonable to ask that the epsilon factor should be 1 whenever the representation is unramified (in GL(1) as well as GL(2) case). 
Jun 2 
awarded  Yearling 
May 15 
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On a result attributed to W. Ljunggren and T. Nagell
According to the Zentralblatt review of Ljunggren's article, the method is to reduce to a (Pell)Fermat equation. zbmath.org/?q=an:0028.00901 
May 10 
awarded  Nice Question 
May 9 
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Elliptic curves and supercuspidal representations of conductor $p^2$
Thanks David, I'm indeed using your algorithm to compute the examples in my comment to @GuestPoster above. I will see if I can find more patterns. 
May 9 
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Elliptic curves and supercuspidal representations of conductor $p^2$
@GuestPoster I've written a Magma code and for $p=11$ it seems to be the case that $\phi$ has order 6, 4, 3, 3 according to whether $v_p(\Delta)$ is 2, 3, 4, 8, so your guess seems right. For $p=5$ I have examples where $(v_p(\Delta),\textrm{ord}(\phi))=(2,3),(2,6),(4,3),(4,6),(8,3),(8,6)$ so $v_p(\Delta)$ seems not sufficient to determine $\phi$. For $p=17$ I have a $(2,3)$example. If you could elaborate on your comment, this would make a nice answer! 
May 8 
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Elliptic curves and supercuspidal representations of conductor $p^2$
Thanks Will for your answer. Do you have a reference for determining the Galois representation from the Kodaira type for $p>5$? 
May 8 
asked  Elliptic curves and supercuspidal representations of conductor $p^2$ 
Jan 27 
awarded  Nice Question 
Jan 10 
awarded  Nice Answer 
Dec 20 
awarded  Nice Answer 
Dec 18 
awarded  Good Answer 
Sep 30 
awarded  Explainer 
Jul 2 
awarded  Curious 
Jun 10 
awarded  Popular Question 
Jun 2 
awarded  Yearling 