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Primes of the form 4*m+3 for which there is no representation as a sum (p*q + p*r + q*r) with three odd primes p <= q <= r.
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%I #7 Jan 22 2024 21:58:08

%S 3,7,11,19,23,31,43,47,59,67,79,83,107,127,139,163,179,223,227,283,

%T 307,347,367,379,443,463,499,523,547,571,619,643,659,683,787,827,883,

%U 907,947,967,1039,1087,1123,1171,1259,1327,1423,1459,1483,1523,1567,1579,1627,1699,1723,1747,1759,1787,1987,1999,2083,2143

%N Primes of the form 4*m+3 for which there is no representation as a sum (p*q + p*r + q*r) with three odd primes p <= q <= r.

%H Antti Karttunen, <a href="/A369249/b369249.txt">Table of n, a(n) for n = 1..20000</a>

%o (PARI) isA369249(n) = ((3==(n%4)) && isprime(n) && !A369054(n)); \\ Needs also program from A369054.

%Y Intersection of A002145 and A369056.

%Y Setwise difference A002145 \ A369250.

%Y Cf. A369054.

%Y Cf. also A189483.

%K nonn

%O 1,1

%A _Antti Karttunen_, Jan 22 2024