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%I #6 Mar 30 2012 18:50:50
%S 1,2,2,4,6,6,8,6,6,14,18,12,12,18,12,18,24,30,34,30,6,12,42,30,30,30,
%T 18,48,30,30,30,66,36,48,24,30,12,54,42,78,54,60,42,48,60,104,72,30,
%U 66,60,66,30,60,30,12,6,30,120,90,60,60,78,60,102,90,90,138,108,36
%N Number d such that (A109833(n)+k*d: 0<=k<=A109831(n)) is an arithmetic progression of primes.
%C a(n) = (A000040(n) - A109833(n)) / A109831(n).
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/PrimeArithmeticProgression.html">Prime Arithmetic Progression</a>
%H <a href="/index/Pri#primes_AP">Index entries for sequences related to primes in arithmetic progressions</a>
%K nonn
%O 2,2
%A _Reinhard Zumkeller_, Jul 04 2005