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Numbers k such that lambda(k) < A011773(k) < phi(k), where lambda is the Carmichael reduced totient function and phi the Euler totient function.
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%I #34 Mar 08 2020 08:33:21

%S 24,48,56,72,80,88,96,112,144,152,160,168,176,184,192,208,216,224,240,

%T 248,264,288,304,320,336,344,352,368,376,384,392,400,416,432,448,456,

%U 464,472,480,496,504,528,536,552,560,568,576,592,608,616,624

%N Numbers k such that lambda(k) < A011773(k) < phi(k), where lambda is the Carmichael reduced totient function and phi the Euler totient function.

%C A002322(k) divides A011773(k) and A011773(k) divides A000010(k).

%H Amiram Eldar, <a href="/A199105/b199105.txt">Table of n, a(n) for n = 1..10000</a>

%t A011773[p_,s_] := (p-1)*p^(s-1); A011773[n_] := {aux=1;Do[aux=LCM[aux,A011773[FactorInteger[n][[i,1]], FactorInteger[n][[i,2]]]], {i,Length[FactorInteger[n]]}]; aux}[[1]]; Select[Range[1000], CarmichaelLambda[#] < A011773[#] < EulerPhi[#]&]

%Y Cf. A000010, A002322, A011773.

%K nonn

%O 1,1

%A _José María Grau Ribas_, Jan 31 2012