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%I #4 Mar 30 2012 18:35:53
%S 4,1,3,2,8,7,7,4,4,9,3,6,6,29,10,5,5,5,8,8,8,8,28,28,7,7,7,7,30,30,30,
%T 4,13,13,27,27,9,9,9,9,9,9,9,19,11,11,11,11,11,11,6,6,6,6,26,26,6,6,
%U 31,23,31,15,15,29,15,29,29,29,15,15,10,10,10,10,10,10,10,10,10,21,12,12,12
%N PrimePi(A066903(n)), the index of A066903(n) in the primes.
%F a(n) = A000720(A066903(n)) = A049084(A066903(n)) . [R. J. Mathar, May 28 2010]
%e a(14)= 29 because prime(29) = 109, and A066903(14) = 109.
%Y Cf. A006577, A066903.
%K nonn
%O 1,1
%A _Michel Lagneau_, May 15 2010
%E Clearer definition from _R. J. Mathar_, May 28 2010