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The number of decades below 10^n whose semiprime pattern is the same as semiprime pattern in the previous decade.
0

%I #6 Dec 12 2012 12:28:30

%S 0,0,7,114,1794,24605

%N The number of decades below 10^n whose semiprime pattern is the same as semiprime pattern in the previous decade.

%e a(3) = 7 because the 7 values less than 10^3 are 104, 389, 435, 438, 529, 658, 884.

%Y Cf. A220063.

%K nonn,base

%O 1,3

%A _Robert G. Wilson v_, _Jonathan Vos Post_, Dec 11 2012