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Smallest odd prime factor of (prime(n)+1)*(prime(n+1)+1)/4.
2

%I #8 Jul 13 2013 12:02:54

%S 3,3,3,3,3,3,3,3,3,3,19,3,3,3,3,3,3,17,3,3,5,3,3,3,3,3,3,3,3,3,3,3,3,

%T 3,3,19,41,3,3,3,3,3,3,3,3,5,7,3,3,3,3,3,3,3,3,3,3,17,3,3,3,3,3,3,3,3,

%U 13,3,3,3,3,3,11,5,3,3,3,3,3,3,3,3,3,5,3,3,3,3,3,3,3,3,3,3,3,3,3,3,131,137

%N Smallest odd prime factor of (prime(n)+1)*(prime(n+1)+1)/4.

%C a(n)=A078701(A079079(n)).

%H Reinhard Zumkeller, <a href="/A079083/b079083.txt">Table of n, a(n) for n = 1..10000</a>

%o (Haskell)

%o a079083 = a078701 . a079079 -- _Reinhard Zumkeller_, Oct 08 2012

%Y Cf. A079084.

%K nonn

%O 1,1

%A _Reinhard Zumkeller_, Dec 22 2002