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A144947 Least a(n) such that p(n)#*(p(n)#+a(n))-1 and p(n)#*(p(n)#+a(n))+1 are twin primes with p(i)#=i-th primorial 4

%I

%S 1,1,4,13,16,1,43,37,126,12,226,149,97,115,33,51,9,428,68,29,34,47,

%T 583,15,502,410,336,283,756,1303,33,793,343,703,1024,1888,728,782,226,

%U 493,1977,3265,567,151,1096,203,77,3255,381,4963

%N Least a(n) such that p(n)#*(p(n)#+a(n))-1 and p(n)#*(p(n)#+a(n))+1 are twin primes with p(i)#=i-th primorial

%H Pierre CAMI, <a href="/A144947/b144947.txt">Table of n, a(n) for n = 1..200</a> [Corrected Oct 16 2008]

%e 2*(2+1)-1=5 prime as 7 so a(1)=1 6*(6+1)-1=41 prime as 43 so a(2)=1

%Y Cf. A144946

%K nonn

%O 1,3

%A _Pierre CAMI_, Sep 26 2008

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Last modified February 3 05:52 EST 2023. Contains 360024 sequences. (Running on oeis4.)