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%I #4 Mar 31 2012 13:50:44
%S 1,1,2,3,2,3,3,4,4,4,3,4,3,6,5,6,4,4,6,5,7,4,6,5,5,7,6,5,7,6,7,8,5,4,
%T 5,7,9,5,2,7,6,7,9,6,5,8,6,7,9,4,10,8,7,9,6,5,6,7,6,7,6,6,7,8,10,7,6,
%U 6,8,6,7,8,9,7,9,7,9,5,8,5,8,7,8,11,9,11,8,10,9,12,10,5,14,6,12,5,3,9,4,6
%N Number of sets of consecutive primes whose arithmetic mean is an integer, the largest prime of a set is n-th prime.
%e a(4) = 3: the largest prime of a set is 4th prime. the three sets are 7/1 = 7, (5+7)/2 = 6, (3+5+7)/3 = 5.
%K easy,nonn
%O 1,3
%A _Naohiro Nomoto_, May 08 2003