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A215233 Primes of the form 4m^2 + 1 such that the next prime of this form is a record distance away. 2

%I

%S 5,37,677,1601,8837,33857,122501,246017,11492101,12503297,2058436901,

%T 6844914757,9813676097,127566122897,707119537217,15058714869137,

%U 779243651884097,1641669426950401,10965274367622437,1269017804759665217,4346851918104880901

%N Primes of the form 4m^2 + 1 such that the next prime of this form is a record distance away.

%C Distance from 4m^2+1 to 4n^2+1 is measured as n-m.

%H Charles R Greathouse IV, <a href="/A215233/b215233.txt">Table of n, a(n) for n = 1..26</a>

%o (PARI) r=0;last=2;forstep(n=4,1e9,2, if(!ispseudoprime(n^2+1),next); if(n-last>r, r=n-last; print1(last^2+1", ")); last=n) \\ _Charles R Greathouse IV_, Apr 09 2013

%Y See A215234 for the next larger prime of the form 4m^2 + 1.

%Y Cf. A214518 (record differences of m), A214519 (values of m).

%K nonn,hard

%O 1,1

%A _T. D. Noe_, Aug 14 2012

%E a(19)-a(21) from _Charles R Greathouse IV_, Apr 09 2013

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Last modified October 3 17:49 EDT 2022. Contains 357237 sequences. (Running on oeis4.)