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A126088
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Least k such that k*(p(n+1)#-p(n)#)-1 and k*(p(n+1)#-p(n)#)+1 are twin primes.
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1
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1, 3, 1, 3, 2, 4, 13, 5, 9, 10, 6, 8, 61, 121, 3, 13, 17, 79, 45, 27, 120, 145, 113, 11, 41, 198, 102, 139, 202, 103, 23, 48, 177, 43, 486, 169, 501, 251, 106, 132, 40, 155, 1890, 116, 584, 107, 629, 241, 1331, 2078, 562, 57, 52, 71, 567, 73, 262, 332, 483, 419, 423
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OFFSET
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1,2
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LINKS
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EXAMPLE
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3*(2*3*5-2*3)-1=71 3*(2*3*5-2*3)+1=73; 71 and 73 twin primes so k(2)=3
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MATHEMATICA
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ktp[n_]:=Module[{k=1}, While[!PrimeQ[k*n-1]||!PrimeQ[k*n+1], k++]; k]; With[ {prmrls=#[[2]]-#[[1]]&/@Partition[FoldList[Times, Prime[Range[ 70]]], 2, 1]}, ktp/@prmrls] (* Harvey P. Dale, Mar 31 2017 *)
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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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