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A266954
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Primes of the form p = a^2 + b^2 where neither |a+b| nor |a-b| is prime.
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2
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41, 113, 313, 353, 613, 653, 677, 761, 857, 977, 1013, 1201, 1301, 1373, 1553, 1613, 1733, 1877, 1913, 2113, 2153, 2213, 2237, 2273, 2297, 2333, 2381, 2477, 2657, 2693, 2713, 3137, 3313, 3329, 3413, 3581, 3593, 3613, 3833, 4013, 4157, 4253, 4373, 4397, 4481
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OFFSET
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1,1
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LINKS
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MAPLE
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filter:= proc(q) local t, p;
if not isprime(q) then return false fi;
t:= op(op(1, GaussInt:-GIfactor(q)));
p:= [abs(Re(t)+Im(t)), abs(Re(t)-Im(t))];
not isprime(p[1]) and not isprime(p[2])
end proc:
select(filter, [seq(i, i=1..10000, 4)]);
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MATHEMATICA
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lst = {}; Do[If[PrimeQ[a^2 + b^2] && ! PrimeQ[a + b] && ! PrimeQ[a - b], AppendTo[lst, a^2 + b^2]], {a, 2, 67}, {b, a -1}]; Take[ Union@ lst, 50] (* Robert G. Wilson v, Jan 06 2016 *)
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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