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A128658 Numbers n such that p(n+1)#-p(n)#+1 is prime where p(i)#=product of first i primes=A002110(i). 5
1, 3, 7, 14, 80, 224, 280, 287, 652, 1509, 2952, 3915 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
LINKS
PROG
(PARI) isok(n) = {my(pp=prod(k=1, n, prime(k))); isprime(pp*prime(n+1) - pp + 1); } \\ Michel Marcus, Sep 20 2019
CROSSREFS
Sequence in context: A266019 A146155 A106363 * A234042 A001203 A154883
KEYWORD
nonn,more
AUTHOR
Pierre CAMI, Mar 19 2007
STATUS
approved

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Last modified March 2 19:19 EST 2024. Contains 370498 sequences. (Running on oeis4.)