%I A076771
%S A076771 18,24,30,36,40,42,48,50,54,56,60,66,70,72,78,80,84,88,90,96,98,100,
%T A076771 102,104,108,110,112,114,120,126,130,132,136,138,140,144,150,152,154,
%U A076771 156,160,162,168,170,174,176,180,182,184,186,190,192,196,198,200,204
%N A076771 Even numbers n representable as the sum of two non-coprime odd composites.
%C A076771 It is conjectured that there is no N such that for all n>N, every even
number is represented.
%e A076771 40=15+25
%o A076771 (PARI) v=vector(5000); vc=1; forstep (n=9,600,2, if (isprime(n),continue,
forstep (j=9,600,2,if (gcd(n,j)>1, if (isprime(j),continue,x=n+j;
fl=true; for (i=1,vc,if (v[i]==x,fl=false; break)); if (fl==true,
v[vc]=x; vc++)))))); print(vc); v=vecsort(vecextract(v,concat("1..",
vc-1)))
%Y A076771 Sequence in context: A076770 A105679 A160810 this_sequence A105093 A162331
A092536
%Y A076771 Adjacent sequences: A076768 A076769 A076770 this_sequence A076772 A076773
A076774
%K A076771 nonn
%O A076771 0,1
%A A076771 Jon Perry (perry(AT)globalnet.co.uk), Nov 14 2002
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