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%I #11 Nov 22 2019 16:22:55
%S 1,2,3,4,24,25,45,59,1238,2635
%N Numbers k such that Product_{j=1..k} prime(j) + Product_{j=k+1..2*k} prime(j) is prime.
%C Based on discussion in primenumbers Yahoo group dated May 12, 2004, with a(9) = 1238 given by _Jens Kruse Andersen_.
%C Numbers k such that A002110(k) + A002110(2*k) / A002110(k) is prime. - _Daniel Suteu_, Nov 22 2019
%H Cashogor, Payam Samidoost, David Cleaver, Jens Kruse Andersen, <a href="/A329532/a329532.txt">Creating Primes</a>, digest of 9 messages in primenumbers Yahoo group, May 12, 2004. [Cached copy]
%o (PARI) for (k=1,100,if (ispseudoprime(prod(j=1,k,prime(j))+prod(j=k+1,k+k,prime(j))),print1(k,", ")))
%Y Cf. A093429.
%K nonn,more,hard
%O 1,2
%A _Hugo Pfoertner_, Nov 15 2019
%E a(10) from _Daniel Suteu_, Nov 22 2019
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