# Greetings from The On-Line Encyclopedia of Integer Sequences! http://oeis.org/

Search: id:a094529
Showing 1-1 of 1

%I A094529 #24 Mar 19 2016 13:08:17
%S A094529 12,24,36,48,60,72,84,96,105,108,120,132,140,144,156,168,180,192,204,
%T A094529 210,216,228,240,252,264,276,280,288,300,312,315,324,336,348,360,372,
%U A094529 384,396,408,420,432,440,444,456,468,480,492,504,516,525,528,540,552,560
%N A094529 Numbers with at least one arithmetic progression of four divisors (not necessarily consecutive).
%C A094529 All multiples of terms are also terms.
%C A094529 a(n) = m*A094530(k) for appropriate m and k.
%H A094529 Alois P. Heinz, <a href="/A094529/b094529.txt">Table of n, a(n) for n = 1..10000</a>
%t A094529 sd4Q[n_]:=Count[Subsets[Divisors[n],{4}],_?(Length[Union[ Differences[ #]]] == 1&)]>0; Select[Range[600],sd4Q] (* _Harvey P. Dale_, Mar 19 2016 *)
%Y A094529 Cf. A091011, A094530.
%Y A094529 See A270571 for another version.
%K A094529 nonn
%O A094529 1,1
%A A094529 _Reinhard Zumkeller_, May 07 2004
%E A094529 Edited by _Harvey P. Dale_ and _Alois P. Heinz_, Mar 18 2016

# Content is available under The OEIS End-User License Agreement: http://oeis.org/LICENSE