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Floor( prime(prime(n))/ prime(n) ).
2

%I #17 Aug 12 2016 17:15:12

%S 1,1,2,2,2,3,3,3,3,3,4,4,4,4,4,4,4,4,4,4,5,5,5,5,5,5,5,5,5,5,5,5,5,5,

%T 5,5,5,5,5,5,5,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,

%U 6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,7,7,7,7,7

%N Floor( prime(prime(n))/ prime(n) ).

%H Charles R Greathouse IV, <a href="/A218461/b218461.txt">Table of n, a(n) for n = 1..10000</a>

%F a(n) = floor(A006450(n)/A000040(n)).

%e [3/2]=1; [5/3]=1; [11/5]=2

%t Floor[Prime[#]/#]&/@Prime[Range[90]] (* _Harvey P. Dale_, Aug 12 2016 *)

%o (PARI) a(n)=prime(n=prime(n))\n \\ _Charles R Greathouse IV_, Oct 31 2012

%o (PARI) apply(p->prime(p)\p, primes(100)) \\ _Charles R Greathouse IV_, Oct 31 2012

%K nonn,easy

%O 1,3

%A _Tyler Carrico_, Oct 30 2012