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Places n where A225867(n)=5.
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%I #20 Jul 05 2013 04:25:30

%S 30,43,45,60,61,73,75,90,97,120,137,151,160,169,173,180,197,240,241,

%T 257,259,311,320,331,347,360,367,389,400,421,480,491,499,569,571,601,

%U 617,640,641,647,709,720,773,800,809,857,881,919,929,947,960,971

%N Places n where A225867(n)=5.

%C The proportion of prime terms has a tendency to increase. For example, 4 from the first 10 terms; 10 from the first 20 terms; 16 from the first 30 terms; 24 from the first 40 terms; 40 from the first 60 terms, 88 from the first 110 terms. We conjecture that this proportion asymptotically tends to 1.

%Y Cf. A225867, A225868, A226977, A227010.

%K nonn

%O 1,1

%A _Vladimir Shevelev_, Jun 29 2013