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%I #7 Oct 19 2017 03:14:15
%S 1,1,3,4,3,4,3,2,2,5,2,4,2,2,6,2,3,4,4,3,5,1,3,3,3,2,3,3,6,2,1,0,0,1,
%T 2,6,2,3,1,7,3,1,1,2,0,1,4,4,2,4,4,0,3,3,4,1,2,4,2,2,1,2,2,2,1,3,2,1,
%U 4,3,2,3,2,3,3,4,5,2,2,5,4,2,2,1,2,2,1,5,0,2,1,2,4,2,4,4,1,5,1,1,1,3,2,1,1
%N a(n) = the number of distinct primes of the form p(n)#/p(i) + p(i).
%C Some of the larger entries may only correspond to probable primes.
%e p(n) is the n-th prime; # denotes primorial (A002110).
%e a(2)=1 because 3#/2+2 and 3#/3+3 are the same prime (5).
%e a(4)=4 because 7#/2+2=107, 7#/3+3=73, 7#/5+5=47, 7#/7+7=37 are four primes.
%o (PARI) p_n_primorial(n) = prod(i=1,n, prime(i)) { for(n=3,200, p=p_n_primorial(n); c=0; for(i=1,n, q=p/prime(i)+prime(i); if(isprime(q),c++)); print1(c,",")) }
%Y Cf. A002110.
%K nonn
%O 1,3
%A _Rick L. Shepherd_, May 31 2003
%E Edited by _Don Reble_, Nov 16 2005
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