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%I #7 Apr 18 2013 16:56:44
%S 2,3,3,3,3,3,5,7,3,11,13,3,11,3,3,3,5,3,3,3,7,19,11,5,7,5,3,23,7,3,3,
%T 5,3,7,5,31,7,3,3,5,17,3,3,3,5,19,3,7,29,7,5,5,61,3,3,3,11,3,3,11,7,3,
%U 3,5,3,5,3,3,3,7,11,11,19,3,61,5,29,7,3,7,17
%N Minimum prime p such that prime(n)*p - 2 is prime.
%C Conjecture: a(n) <= prime(n). Tested to n=10000.
%H T. D. Noe, <a href="/A103959/b103959.txt">Table of n, a(n) for n = 1..10000</a>
%e Prime(1)*2-2=2 is prime, so a(1)=2;
%e Prime(2)*3-2=7 is prime, so a(2)=3;
%t Table[p=Prime[n]; k=1; pk=Prime[k]; cp=p*pk-2; While[ !PrimeQ[cp], k=k+1; pk=Prime[k]; cp=p*pk-2]; pk, {n, 100}]
%K easy,nonn
%O 1,1
%A _Lei Zhou_, Feb 22 2005
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