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A178045 Numbers of semiprimes between consecutive even numbers that are not semiprimes. 0

%I

%S 0,2,2,2,0,0,2,2,0,0,3,2,0,0,1,1,1,0,1,2,1,1,0,1,0,1,1,0,1,3,0,1,3,0,

%T 0,0,0,1,0,1,0,1,2,3,0,0,1,0,2,0,0,3,2,0,0,0,1,2,1,0,1,1,0,0,0,2,0,1,

%U 1,1,0,0,1,0,0,3,2,1,0,3,3,1,0,1,0,0,0,1,1,0,0,0,0,1,1,0,2,0,1,1,1,1,0,0,1

%N Numbers of semiprimes between consecutive even numbers that are not semiprimes.

%C Numbers of semiprimes between A176100(n) and A176100(n+1) where A176100 is twice the n-th nonprime numbers.

%e a(1)=0 because 2*A141468(1)=0<2=2*A141468(2); a(2)=2 because 2*A141468(2)=2<4(semiprime)<6(semiprime)<8=2*A141468(3).

%Y Cf. A001358, A141468, A176851.

%K nonn

%O 1,2

%A _Juri-Stepan Gerasimov_, May 18 2010

%E a(66) and a(67) corrected by _R. J. Mathar_, May 28 2010

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Last modified March 7 10:38 EST 2021. Contains 341869 sequences. (Running on oeis4.)