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A115986
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Primes p such that the average of p and nextprime(p) is a power of 3.
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4
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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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Nextprime(387420479) = 387420499 and (387420479 + 387420499)/2 = 387420489 = 3^18.
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PROG
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(PARI) lista(nn) = for(k=1, nn, if(precprime(3^k-1)+nextprime(3^k+1)==2*3^k, print1(precprime(3^k-1), ", "))); \\ Jinyuan Wang, Feb 26 2020
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CROSSREFS
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KEYWORD
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nonn,changed
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AUTHOR
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STATUS
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approved
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