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Search: id:A076771
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| A076771 |
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Even numbers n representable as the sum of two non-coprime odd composites. |
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+0
1
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| 18, 24, 30, 36, 40, 42, 48, 50, 54, 56, 60, 66, 70, 72, 78, 80, 84, 88, 90, 96, 98, 100, 102, 104, 108, 110, 112, 114, 120, 126, 130, 132, 136, 138, 140, 144, 150, 152, 154, 156, 160, 162, 168, 170, 174, 176, 180, 182, 184, 186, 190, 192, 196, 198, 200, 204
(list; graph; listen)
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OFFSET
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0,1
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COMMENT
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It is conjectured that there is no N such that for all n>N, every even number is represented.
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EXAMPLE
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40=15+25
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PROGRAM
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(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)))
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CROSSREFS
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Sequence in context: A086473 A076770 A105679 this_sequence A105093 A092536 A125261
Adjacent sequences: A076768 A076769 A076770 this_sequence A076772 A076773 A076774
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KEYWORD
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nonn
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AUTHOR
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Jon Perry (perry(AT)globalnet.co.uk), Nov 14 2002
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