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%I #13 Jan 25 2024 07:57:39
%S 27,39,51,55,71,75,87,91,95,103,111,119,123,131,135,147,151,155,167,
%T 183,187,191,195,199,203,211,215,231,239,247,251,255,263,267,271,275,
%U 287,291,299,311,315,327,331,335,343,351,355,359,363,371,375,383,391,395,407,411,419,423,431,435,439,447,451,455,459
%N Numbers that have at least one representation as a sum (p*q + p*r + q*r) with three odd primes p <= q <= r.
%C By necessity all terms are of the form 4m+3 (in A004767).
%H Antti Karttunen, <a href="/A369251/b369251.txt">Table of n, a(n) for n = 1..20000</a>
%F {k | A369054(k) > 0}.
%o (PARI) isA369251(n) = if(3!=(n%4),0, my(v = [3,3], ip = #v, r); while(1, r = (n-(v[1]*v[2])) / (v[1]+v[2]); if(r < v[2], ip--, ip = #v; if(1==denominator(r) && isprime(r), return(1))); if(!ip, return(0)); v[ip] = nextprime(1+v[ip]); for(i=1+ip,#v,v[i]=v[i-1])));
%Y Complement of A369464.
%Y Sequence A369252 sorted into ascending order, with duplicates removed.
%Y Setwise difference A004767 \ A369056.
%Y Subsequence of A239433.
%Y Cf. A369054, A369055.
%Y Cf. A369250 (primes in this sequence).
%K nonn
%O 1,1
%A _Antti Karttunen_, Jan 22 2024
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