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A128658
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Numbers n such that p(n+1)#-p(n)#+1 is prime where p(i)#=product of first i primes=A002110(i).
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5
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1, 3, 7, 14, 80, 224, 280, 287, 652, 1509, 2952, 3915
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OFFSET
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1,2
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LINKS
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PROG
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(PARI) isok(n) = {my(pp=prod(k=1, n, prime(k))); isprime(pp*prime(n+1) - pp + 1); } \\ Michel Marcus, Sep 20 2019
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CROSSREFS
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KEYWORD
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nonn,more
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AUTHOR
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STATUS
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approved
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