%I #15 Aug 03 2014 14:01:32
%S 10,15,39,35,83,39,143,131,129,83,179,111,263,143,243,227,479,129,839,
%T 203,381,179,463,363,503,263,543,339,641,243,1367,547,597,479,563,219,
%U 965,839,549,563,1643,381,1551,839,993,463,1883,531,1571,503,819,523
%N Smallest sum of three distinct primes of the form n*k+1.
%H Vincenzo Librandi, <a href="/A194267/b194267.txt">Table of n, a(n) for n = 1..1000</a>
%e a(1) = 2+3+5 = 10.
%e a(2) = 3+5+7 = 15.
%e a(3) = 7+13+19 = 39.
%e a(4) = 5+13+17 = 35.
%e a(5) = 11+31+41 = 83.
%e a(6) = 7+13+19 = 39.
%t Table[ps = Select[Table[n*k + 1, {k, 100}], PrimeQ, 3]; If[Length[ps] == 3, Total[ps], 0], {n, 100}] (* _T. D. Noe_, Oct 21 2011 *)
%Y Cf. A077318, A132810, A193873, A194266.
%K nonn
%O 1,1
%A _Omar E. Pol_, Sep 03 2011
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