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%I #12 Aug 12 2012 19:02:07
%S 0,0,1,2,2,2,3,4,4,5,7,10,11,16,23,28,43,62,106,177,309,483,795,1305,
%T 2105,3525,5923,10096,17259,30004
%N Number of prime quadruples with smallest member < 2^n.
%C Prime quadruples (A007530) are numbers n such that n, n+2, n+6, n+8 are all prime.
%e a(3) = 1 because there is only one prime quadruple below 2^3, namely {5, 7, 11, 13}.
%e a(4) = 2 because there are two prime quadruples below 2^4: the aforementioned and {11, 13, 17, 19}.
%t (* First run program for A007530 *) Table[Length[Select[A007530, # < 2^n &]], {n, 14}] (* _Alonso del Arte_, Aug 12 2012 *)
%Y Cf. A050258, similar definition but with powers of 10 instead of 2.
%Y Cf. A007530, A014561, A112540.
%Y Cf. A033843, A007053.
%K nonn
%O 1,4
%A _Alex Ratushnyak_, Aug 12 2012