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Numbers not appearing in A178133, which gives the number of odd semiprimes between consecutive squares.
2

%I #20 Mar 24 2017 00:47:53

%S 25,33,63,66,75,88,191,269,285,309,348,379,399,400,404,413,437,443,

%T 456,548,553,594,616,638,675,684,702,724,764,810,819,823,829,843,897,

%U 901,906,907,1000,1031,1041,1068,1075,1159,1200,1230,1241,1255,1279,1280,1281,1300,1323,1332

%N Numbers not appearing in A178133, which gives the number of odd semiprimes between consecutive squares.

%t lst={}; k=0; s=4; Do[If[OddQ[n]&&Last/@FactorInteger[n]=={1,1}, If[n<s^2, k++, AppendTo[lst,k]; k=1;s++]], {n,2*10^8}]; Complement[Range@3000, Union@lst]

%Y Cf. A178133.

%K nonn

%O 1,1

%A _Vladimir Joseph Stephan Orlovsky_, Apr 20 2011

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Last modified September 23 01:59 EDT 2024. Contains 376140 sequences. (Running on oeis4.)