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%I #10 Mar 11 2019 20:48:07
%S 0,0,1,1,1,2,2,0,3,4,2,0,5,0,2,1,1,3,3,2,5,0,3,0,1,2,1,4,0,0,2,0,2,1,
%T 2,0,3,2,0,1,1,0,1,0,0,1,2,0,0,2,1,2,3,0,0,0,1,0,0,1,4,0,1,2,0,0,0,4,
%U 1,1,1,0,1,2,1,1,1,3,2,1,2,1,1,0,2,1,0,1,0,0,2,4,2,1,0,0,3,0,4,1,3,0,0,1,0
%N a(n) is the number of successive primorials A002110(i) larger than prime(n) that need to be tried before sum prime(n)+A002110(i) is found to be composite.
%C See comments and examples in A324656.
%H Antti Karttunen, <a href="/A324657/b324657.txt">Table of n, a(n) for n = 1..25000</a>
%H <a href="/index/Pri#primorial_numbers">Index entries for sequences related to primorial numbers</a>
%F a(n) = A324656(A000040(n)).
%o (PARI)
%o A002110(n) = prod(i=1,n,prime(i));
%o A235224(n, p=2) = if(!n, n, 1+A235224(n\p, nextprime(p+1)));
%o A324656(n) = { my(k=0,b=A235224(n)); while(isprime(n+A002110(b+k)), k++); (k); };
%o A324657(n) = A324656(prime(n));
%Y Cf. A000040, A002110, A324656.
%K nonn
%O 1,6
%A _Antti Karttunen_, Mar 11 2019
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