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%I #12 May 21 2016 23:38:19
%S 10,20,30,60,90,120,180,240,360,480,540,600,720,1080,1440,2160,4320
%N Ramanujan's largely composite numbers having 5 as the greatest prime divisor.
%C By the theorem in comment in A273015, the sequence is finite.
%t a = {}; b = {0}; Do[If[# >= Max@ b, AppendTo[a, k] && AppendTo[b, #]] &@ DivisorSigma[0, k], {k, 10^7}]; Select[a, FactorInteger[#][[-1, 1]] == 5 &] (* _Michael De Vlieger_, May 13 2016 *)
%Y Cf. A067128, A273015.
%K nonn,fini,full
%O 1,1
%A _Vladimir Shevelev_ and _Peter J. C. Moses_, May 13 2016