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%I #8 Jan 09 2021 09:56:37
%S 1,2,3,8
%N Numbers k such that 1 + Product_{j=1..k} prime(j)^prime(k-j+1) is prime.
%C A131958 gives the corresponding primes.
%e 1 + (2^5)*(3^3)*(5^2) = 21601 is the prime for the term 3.
%o (PARI) isok(k) = isprime(1 + prod(j=1, k, prime(j)^prime(k-j+1))); \\ _Michel Marcus_, Jan 09 2021
%Y Cf. A131958.
%K hard,nonn,more
%O 1,2
%A _Rick L. Shepherd_, Aug 01 2007
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