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%I #4 Mar 31 2012 14:42:50
%S 0,0,0,0,0,7,11,0,15,21,21,31,7,11,35,9,17,17,61,9,21,23,23,77,7,19,
%T 97,101,91,19,13,41,25,127,47,139,21,17,31,11,167,13,37,11,61,25,39,7,
%U 13,73,9,227,25,239,35,15,9,29,271,269,37,25,7,61,59,27,21,13,11,113,113
%N a(n) = smallest k such that prime(n+2) = prime(n) + (prime(n) mod k), or 0 if no such k exists.
%H Remi Eismann, <a href="/A133346/b133346.txt">Table of n, a(n) for n = 1..10000</a>
%e For n = 1 we have prime(n) = 2, prime(n+2) = 5; there is no k such that 5 - 2 = 3 = (2 mod k), hence a(1) = 0.
%e For n = 6 we have prime(n) = 13, prime(n+2) = 19; 7 is the smallest k such that 19 - 13 = 6 = (13 mod k), hence a(6) = 7.
%e For n = 30 we have prime(n) = 113, prime(n+2) = 131; 19 is the smallest k such that 131 - 113 = 18 = (113 mod k), hence a(30) = 19.
%Y Cf. A000040, A117078, A117563, A001223, A118534, A020639, A090369, A090368, A130533, A130650, A130703, A130889, A130882.
%K nonn
%O 1,6
%A _Rémi Eismann_, Oct 20 2007
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