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%I #8 Nov 21 2013 12:49:39
%S 7,21,42,56,84,105,154,210,252,399,546,840,1722
%N Strictly positive numbers n such that (42*n)/(42+n) is an integer.
%t f[a_,b_]:=(a*b)/(a+b); a=42;lst={};Do[If[f[a,n]==IntegerPart[f[a,n]],AppendTo[lst,n]],{n,9!}];lst
%t Select[Range[2000], Divisible[42 #, 42 + #] &] (* _Harvey P. Dale_, May 09 2012 *)
%Y Cf. A162688, A162689, A162690, A162691, A162692, A162693, A162694, A162817
%Y Cf. A127730 - _Franklin T. Adams-Watters_, Aug 07 2009
%K nonn,fini,full
%O 1,1
%A _Vladimir Joseph Stephan Orlovsky_, Jul 13 2009
%E Keywords fini and full added by _Franklin T. Adams-Watters_, Aug 07 2009
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