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A262225 Euclid-Mullin sequence: a(1) = 5, a(n+1) is largest prime factor of Product_{k=1..n} a(k) + 1. 1

%I

%S 5,3,2,31,19,431,3457,24907963,250198320553451,

%T 164072502171958410481596412086571,

%U 15268641997545743809809010755124846521575738536063

%N Euclid-Mullin sequence: a(1) = 5, a(n+1) is largest prime factor of Product_{k=1..n} a(k) + 1.

%C This is similar to A000946 but starting a(1) = 5.

%H Ben Meekins, <a href="/A262225/b262225.txt">Table of n, a(n) for n = 1..12</a>

%t a = {5}; Do[AppendTo[a, FactorInteger[Product[a[[k]], {k, n - 1}] + 1][[-1, 1]]], {n, 2, 11}]; a (* _Michael De Vlieger_, Sep 15 2015 *)

%Y Cf. A000946.

%K nonn

%O 1,1

%A _Ben Meekins_, Sep 15 2015

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Last modified October 21 02:41 EDT 2018. Contains 316405 sequences. (Running on oeis4.)