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Least number m such that integer part of sigma(m)/phi(m) equals n.
2

%I #11 Oct 15 2013 22:31:18

%S 1,3,2,10,20,6,12,42,30,60,120,210,630,420,840,2520,10080,9240,27720,

%T 55440,120120,360360,720720,2162160,6126120,12252240,36756720,

%U 116396280,232792560,698377680,2677114440,5354228880,26771144400,155272637520,465817912560

%N Least number m such that integer part of sigma(m)/phi(m) equals n.

%C a(36) <= 1552726375200. a(37) <= 9316358251200. - _Donovan Johnson_, Oct 18 2012

%F a(n)=Min{x : Floor[A000203(x)/A000010(x)]=n}

%t t=Table[0, {100}]; Do[c=Floor[DivisorSigma[1, n]/EulerPhi[n]]; If[c<101&&t[[c]]== 0, t[[c]]=n], {n, 1, 100000}]; t

%Y Cf. A000203, A000010, A070032.

%K nonn

%O 1,2

%A _Labos Elemer_, Apr 15 2002

%E Two more terms from _Labos Elemer_, May 18 2004

%E a(30)-a(33) from _Donovan Johnson_, Apr 14 2010

%E a(34)-a(35) from _Donovan Johnson_, Oct 18 2012