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a(n) is the third term in Euclid-Mullin (EM) prime sequence initiated with n-th prime.
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%I #10 Mar 13 2015 23:08:16

%S 7,7,11,3,23,3,5,3,47,59,3,3,83,3,5,107,7,3,3,11,3,3,167,179,3,7,3,5,

%T 3,227,3,263,5,3,13,3,3,3,5,347,359,3,383,3,5,3,3,3,5,3,467,479,3,503,

%U 5,17,7,3,3,563,3,587,3,7,3,5,3,3,5,3,7,719,3,3,3,13,19,3,11,3,839,3,863

%N a(n) is the third term in Euclid-Mullin (EM) prime sequence initiated with n-th prime.

%F a(n)= a(n-1)+ A008472(a(n-1)) - _Ctibor O. Zizka_, May 26 2008

%e First term is p[n], 2nd equals 2; 3rd term is given here as largest p-divisor of 2p+1 [occasionally safe primes, A005385];

%e 4th terms listed in A051614; further terms are in A094461-A094463.

%t a[x_]:=First[Flatten [FactorInteger[Apply[Times, Table[a[j], {j, 1, x-1}]]+1]]]; ta=Table[0, {168}]; a[1]=1; Do[{a[1]=Prime[j], el=10}; Print[a[el]; ta[[j]]=a[el]; j++ ], {j, 1, 168}]; ta

%Y Cf. A000945, A005385, A051614-A051616, A051308 - A051335, A093778-A093782, A094152/A094153.

%Y Except for first term [which is A000945(3)], the same as A023592.

%K nonn

%O 1,1

%A _Labos Elemer_, May 06 2004