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%I #12 Mar 31 2012 14:00:56
%S 0,2,0,1,3,0,2,4,1,0,2,2,5,4,0,3,3,6,5,1,0,1,3,3,1,7,6,0,2,4,4,2,8,7,
%T 1,0,1,1,7,5,11,10,4,3,0,2,2,8,6,12,11,5,4,1,0,1,3,6,3,5,3,12,11,8,7,
%U 0,2,4,7,4
%N Triangle read by rows: R(n,k)= semiprime(n) mod semiprime(k), 0<k<=n.
%C Row sums are 0, 2, 4, 7, 13, 18, 28,...
%e 0,
%e 2,0;
%e 1,3,0;
%e 2,4,1,0;
%e 2,2,5,4,0;
%e 3,3,6,5,1,0;
%e 1,3,3,1,7,6,0;
%e 2,4,4,2,8,7,1,0;
%t SemiprimeQ[n_Integer] := If[Abs[n]<2, False, (2==Plus@@Transpose[FactorInteger[Abs[n]]][[2]])]; sp = Select[Range[100], SemiprimeQ]; Flatten[Table[Mod[sp[[n]], sp[[Range[n]]]], {n,Length[sp]}]]
%Y Cf. A001358, A173655.
%K nonn,tabl,easy
%O 1,2
%A _Juri-Stepan Gerasimov_, Nov 28 2010
%E 46th term corrected by _D. S. McNeil_, Nov 24 2010
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