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Number of twin prime pairs < square of n-th prime.
3

%I #14 Nov 21 2013 12:45:45

%S 0,2,4,6,10,12,19,21,25,33,35,46,53,56,67,80,93,98,117,128,131,146,

%T 160,174,195,210,217,227,233,244,286,298,325,331,376,386,406,423,444,

%U 467,492,505,554,561,581,589,641,700,723,732,748,780,789,835,868,895,938,945,975

%N Number of twin prime pairs < square of n-th prime.

%H Donovan Johnson, <a href="/A000885/b000885.txt">Table of n, a(n) for n = 1..10000</a>

%t With[{tpps=Select[Partition[Prime[Range[10000]],2,1],Last[#]- First[#] == 2&]}, Table[ Count[tpps,_?(Last[#]<Prime[n]^2&)],{n,60}]] (* _Harvey P. Dale_, Aug 11 2011 *)

%Y Cf. A000879.

%K nonn

%O 1,2

%A gandalf(AT)hrn.office.ssi.net (James D. Ausfahl)

%E More terms from _David W. Wilson_