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%I #17 Mar 20 2018 12:36:14
%S 37,43,71,89,101,127,139,149,167,181,191,193,197,251,313,379,449,523,
%T 601,683,769,859,953,1051,1153,1259,1483,1601,1723,1979,2113,2251,
%U 2393,2539,2689,2843,3001,3163,3329,3499,3673,3851,4219,4409,4603,4801,5003
%N Primes of form abs(2*n^2-199).
%D C. Clawson, Mathematical Mysteries, Plenum Press, 1996, p. 173
%t Select[Abs[2*Range[-15,70]^2-199],PrimeQ]//Union (* _Harvey P. Dale_, Mar 20 2018 *)
%o (PARI) isok(n) = isprime(n) && (n != 199) && (issquare((n+199)/2) || issquare((199-n)/2)); \\ _Michel Marcus_, Sep 28 2013
%K nonn
%O 1,1
%A _Felice Russo_
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