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Primes of form 4*p^2 + 1, p prime.
5

%I #9 Aug 03 2014 14:31:48

%S 17,37,101,197,677,5477,8837,17957,21317,42437,98597,106277,148997,

%T 217157,401957,454277,1196837,1378277,1674437,1705637,1833317,1865957,

%U 2390117,2735717,3118757,3147077,3587237,3865157,4104677,4519877

%N Primes of form 4*p^2 + 1, p prime.

%H T. D. Noe, <a href="/A052292/b052292.txt">Table of n, a(n) for n = 1..10000</a>

%F q = 4p^2 + 1 primes

%e a(10) = 42437 = 4*103*103 + 1, where 103 is the generating prime.

%t Select[Prime[Range[350000]], PrimeQ[Sqrt[(#-1)/4]]&] (* _Harvey P. Dale_, Feb 20 2011 *)

%Y Cf. A052291.

%K nonn

%O 1,1

%A _Labos Elemer_, Feb 08 2000