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A263282
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Numbers n such that 6n is in A002822 but n is not.
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2
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63, 65, 88, 98, 102, 133, 157, 163, 185, 193, 198, 203, 208, 210, 233, 245, 250, 262, 310, 340, 380, 387, 413, 437, 457, 462, 473, 478, 483, 493, 507, 508, 515, 530, 585, 600, 627, 635, 640, 647, 658, 662, 677, 718, 742, 765, 772, 793, 795, 830, 847, 857
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OFFSET
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1,1
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COMMENTS
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To use Dinculescu's terminology (see links): non-ranks n such that 6n is a twin-rank.
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LINKS
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EXAMPLE
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Take n = 63; then 6n = 378 and 36n = 2268; now 379, 2267, and 2269 are prime, but 377 = 13 x 29.
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MATHEMATICA
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PROG
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(Magma) IsInA2822:=func<n|IsPrime(6*n-1)and IsPrime(6*n+1)>;
[n:n in[1..10^3]|not IsInA2822(n)and IsInA2822(6*n)];
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CROSSREFS
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KEYWORD
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nonn,easy
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AUTHOR
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STATUS
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approved
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