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A078884
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Greater member p of a twin prime pair such that p-1 is 3-smooth.
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3
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5, 7, 13, 19, 73, 109, 193, 433, 1153, 2593, 139969, 472393, 786433, 995329, 57395629, 63700993, 169869313, 4076863489, 10871635969, 2348273369089, 56358560858113, 79164837199873, 84537841287169, 150289495621633
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OFFSET
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1,1
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LINKS
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FORMULA
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EXAMPLE
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MAPLE
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N:= 10^100:
sort(select(t -> isprime(t) and isprime(t-2),
[seq(seq(1+2^i*3^j, i=1..ilog2(floor(N/3^j))), j=0..floor(log[3](N)))])); # Robert Israel, May 14 2018
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MATHEMATICA
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1 + Select[With[{n = 10^15}, Sort@ Flatten@ Table[2^p * 3^q, {p, 0, Log2@ n}, {q, 0, Log[3, n/(2^p)]}] ], AllTrue[# + {-1, 1}, PrimeQ] &] (* Michael De Vlieger, May 14 2018 *)
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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