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A128657
Numbers k such that p(k+1)# - p(k)# - 1 is prime where p(i)# = product of first i primes = A002110(i).
5
1, 2, 3, 4, 8, 24, 35, 56, 79, 132, 281, 342, 631, 1350, 4929, 5952, 8128
OFFSET
1,2
PROG
(PARI) isok(n) = {my(pp=prod(k=1, n, prime(k))); isprime(pp*prime(n+1) - pp -1); } \\ Michel Marcus, Sep 20 2019
KEYWORD
nonn,more
AUTHOR
Pierre CAMI, Mar 19 2007
EXTENSIONS
a(17) from Michael S. Branicky, Oct 06 2024
STATUS
approved