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Smallest prime divisor of prime(n) + prime(n+1) + prime(n+2).
1

%I #10 Dec 17 2012 13:15:38

%S 2,3,23,31,41,7,59,71,83,97,109,11,131,11,3,173,11,199,211,223,5,251,

%T 269,7,7,311,11,7,349,7,5,11,5,439,457,3,487,503,3,13,19,5,7,19,607,3,

%U 661,7,13,701,23,17,7,3,3,11,19,829,29,857,883,911,7,941

%N Smallest prime divisor of prime(n) + prime(n+1) + prime(n+2).

%H Zak Seidov, <a href="/A220569/b220569.txt">Table of n, a(n) for n = 1..1000</a>

%e a(6) = 7 because prime(6) + prime(6+1) + prime(6+2) = 13 + 17 + 19 = 49 and the smallest prime factor of 49 is 7.

%o (PARI) {a=2; b=3; c=5; for(n=1, 100, s=a+b+c;

%o dv=divisors(s); print1(dv[2]", "); a=b; b=c; c=nextprime(c+2))}

%Y Cf. A034961, A034962, A073681.

%K nonn

%O 1,1

%A _Zak Seidov_, Dec 16 2012