Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).
%I #11 Oct 29 2014 16:14:16
%S 2,7,13,19,31,37,83,131,67,317,277,109,367,127,139,157,293,181,199,
%T 211,509,709,911,443,677,503,307,2459,761,337,379,653,409,971,743,
%U 3169,1097,487,499,863,1609,541,571,577,983,1789,631,1559,6581,1601,1163,1193,3613,751,769,787,2957
%N Least prime p>=prime(n) such that p + 2 == 0 (mod prime(n)).
%H Zak Seidov, <a href="/A249419/b249419.txt">Table of n, a(n) for n = 1..1000</a>
%o (PARI) a(n) = {pn = prime(n); forprime(p = pn,, if (((p+2) % pn) == 0, return (p)););} \\ _Michel Marcus_, Oct 29 2014
%K nonn
%O 1,1
%A _Zak Seidov_, Oct 28 2014