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A021005
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Let q_k=p(p+2) be product of k-th pair of twin primes; sequence gives values of p such that (q_k)^2 > q_{k-i}q_{k+i} for all 1 <= i <= k-1.
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2
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3, 11, 29, 59, 101, 137, 179, 191, 227, 419, 521, 569, 599, 809, 821, 1019, 1229, 1277, 1289, 1607, 1667, 1871, 2081
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OFFSET
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1,1
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LINKS
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EXAMPLE
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E.g. (11*13)^2 > (5*7)*(17*19): (11*13)^2 > (3*5)*(29*31).
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PROG
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(PARI) twins=List(); p=3; forprime(q=5, 1e5, if(q-p==2, listput(twins, q)); p=q); for(k=1, (#twins+1)\2, for(i=1, k-1, if(twins[k]^2 < twins[k-i]*twins[k+i], next(2))); print1(twins[k]-2", ")) \\ Charles R Greathouse IV, Apr 02 2014
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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