non-asymptotic Bertrand-type theorems for arithmetic progression - MathOverflow most recent 30 from http://mathoverflow.net2013-05-21T16:58:07Zhttp://mathoverflow.net/feeds/question/55355http://www.creativecommons.org/licenses/by-nc/2.5/rdfhttp://mathoverflow.net/questions/55355/non-asymptotic-bertrand-type-theorems-for-arithmetic-progressionnon-asymptotic Bertrand-type theorems for arithmetic progressionFedor Petrov2011-02-13T23:24:07Z2011-02-18T18:54:25Z
<p>It is well known that primes of form $4k+3$, call them $3=q_1 < q_2 < \dots$ satisfy $q_{n+1}/q_n\rightarrow 1$ (and even $q_n=\frac{n}{2\log n}(1+o(1))$). I would be glad to see results of Dusart-type (http://mathoverflow.net/questions/2724/strong-bertrand-postulate/2729#2729) with concrete bounds for $N$ such that $q_{n+1} < 1.1 q_n$ provided $q_n > N$ or something like this (I am not sure that I need a multiple exactly $1.1$)</p>
http://mathoverflow.net/questions/55355/non-asymptotic-bertrand-type-theorems-for-arithmetic-progression/55369#55369Answer by Felipe Voloch for non-asymptotic Bertrand-type theorems for arithmetic progressionFelipe Voloch2011-02-14T00:38:58Z2011-02-14T00:38:58Z<p>Have a look at (Satz 9 and the preceeding calculations):</p>
<p>1935-10 P. Erdõs: Über die Primzahlen gewisser arithmetischer Reihen (in German), Math. Z. 39 (1935), 473--491; Zentralblatt 10,293. </p>
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