cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A162691 Strictly positive numbers n such that 24*n/(24+n) is an integer.

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%I A162691 #6 Jul 30 2021 16:44:04
%S A162691 8,12,24,40,48,72,120,168,264,552
%N A162691 Strictly positive numbers n such that 24*n/(24+n) is an integer.
%C A162691 The 24th row of A127730.
%C A162691 The ansatz 24*n/(24+n)=j (any integer j) yields n=24*j/(24-j) which demonstrates that the sequence is finite if n>=0. [R. J. Mathar, Jul 13 2009]
%t A162691 f[a_,b_]:=(a*b)/(a+b); a=24;lst={};Do[If[f[a,n]==IntegerPart[f[a,n]],AppendTo[lst,n]],{n,9!}];lst
%t A162691 Select[Range[600],IntegerQ[(24#)/(24+#)]&] (* _Harvey P. Dale_, Jul 30 2021 *)
%Y A162691 Cf. A162688, A162689, A162690
%Y A162691 Cf. A127730. [From _Franklin T. Adams-Watters_, Aug 07 2009]
%K A162691 nonn,fini,full
%O A162691 1,1
%A A162691 _Vladimir Joseph Stephan Orlovsky_, Jul 10 2009
%E A162691 Edited by _R. J. Mathar_, Jul 13 2009