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Greatest number of primes < prime(n) forming an arithmetic progression such that also prime(n) is a term.
3

%I #6 Mar 30 2012 18:50:50

%S 1,1,2,2,1,2,2,3,4,2,1,3,3,2,4,3,2,2,2,2,3,3,2,3,3,3,3,2,3,4,4,2,3,3,

%T 3,5,3,3,4,2,3,3,3,4,3,2,3,4,3,3,3,3,4,5,3,3,4,2,3,4,4,3,5,3,3,3,2,3,

%U 3,5,3,3,4,2,3,4,4,3,3,3,4,3,3,3,4,4,3,3,5,3,4,3,3,2,3,5,4,3,3,3,2,3

%N Greatest number of primes < prime(n) forming an arithmetic progression such that also prime(n) is a term.

%C a(n) = (A000040(n) - A109833(n)) / A109832(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 2,3

%A _Reinhard Zumkeller_, Jul 04 2005