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A128944
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Numbers n such that the smallest prime > 2^n is a twin prime member.
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1
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1, 2, 3, 4, 9, 10, 16, 23, 229, 245, 266, 338, 628, 4118
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listen;
history;
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internal format)
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OFFSET
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1,2
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LINKS
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FORMULA
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EXAMPLE
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For n=4, 17 is the smallest prime > 2^4 and is a member of the twin prime pair 17, 19.
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MATHEMATICA
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Select[Range[4200], AnyTrue[NextPrime[2^#]+{2, -2}, PrimeQ]&] (* Harvey P. Dale, Mar 07 2023 *)
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PROG
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(PARI) g(n, b)=for(x=1, n, y=nextprime(b^x); if(ispseudoprime(y+2), print1(x", ")))
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CROSSREFS
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KEYWORD
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hard,more,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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