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A117092
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Numbers n such that nextprime(2*n) > 2*nextprime(n) (here nextprime = A007918; if p is prime then nextprime(p) = p).
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1
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2, 3, 4, 5, 7, 10, 11, 12, 13, 16, 17, 19, 22, 23, 27, 28, 29, 31, 37, 40, 41, 42, 43, 45, 46, 47, 52, 53, 57, 58, 59, 60, 61, 66, 67, 70, 71, 72, 73, 79, 82, 83, 87, 88, 89, 97, 100, 101, 102, 103, 106, 107, 108, 109, 112, 113, 126, 127, 129, 130, 131, 136
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OFFSET
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1,1
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COMMENTS
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LINKS
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EXAMPLE
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nextprime(2*12)=29 and nextprime(2)*nextprime(12)=2*13 then 12 is member because 29>26.
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MAPLE
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select(t -> nextprime(2*t) > 2*nextprime(t-1), [$1..100]); # Robert Israel, Mar 30 2016
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MATHEMATICA
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Select[Range@100, NextPrime[2 #] > 2 NextPrime[# - 1] &] (* Ivan Neretin, Mar 30 2016 *)
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PROG
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(PARI) for(i=1, 100, if(nextprime(2*i)<nextprime(2)*nextprime(i), print1(i, ", ")))
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CROSSREFS
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KEYWORD
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easy,nonn
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AUTHOR
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Mohammed Bouayoun (mohammed.bouayoun(AT)sanef.com), Apr 18 2006
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EXTENSIONS
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STATUS
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approved
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