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%I #4 Mar 31 2012 12:38:25
%S 4,6,12,24,36,60,132
%N Strictly positive numbers n such that 12*n/(12+n) are integers.
%C The 12 row of A127730.
%C The ansatz 12*n/(12+n)=j (any integer j) yields n=12*j/(12-j) which demonstrates that the sequence is finite if n>=0. [R. J. Mathar, Jul 13 2009]
%t f[a_,b_]:=(a*b)/(a+b); a=12;lst={};Do[If[f[a,n]==IntegerPart[f[a,n]],AppendTo[lst,n]],{n,9!}];lst
%Y Cf. A127730. [From _Franklin T. Adams-Watters_, Aug 07 2009]
%K nonn,fini,full
%O 1,1
%A _Vladimir Joseph Stephan Orlovsky_, Jul 10 2009
%E Edited by _R. J. Mathar_, Jul 13 2009
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