A083247 - OEIS

%I #9 Oct 15 2013 22:31:59

%S 14,20,21,22,26,27,28,32,33,34,35,38,39,44,45,46,49,51,52,55,57,58,62,

%T 63,64,65,68,69,74,75,76,77,81,82,85,86,87,91,92,93,94,95,99,106,111,

%U 115,116,117,118,119,121,122,123,124,125,128,129,133,134,135,141,142

%N Numbers satisfying the following inequalities: A000010(n)>A045763(n)>A000005(n).

%e n=99: d[n]=6,phi[n]=60,unrelateds[n]=99-6-60+1=34 so

%e 60>34>6 holds; primes are not here A045763[p]=0 < A000005[p]=2.

%t Do[r=EulerPhi[n]; d=DivisorSigma[0, n]; u=n-r-d+1; If[Greater[r, u]&&Greater[u, d], Print[n, {d, r, u}]], {n, 1, 1000}]

%o (PARI) is(n)=my(r=eulerphi(n),d=numdiv(n),u=n-r-d+1); r>u && u>d \\ _Charles R Greathouse IV_, Feb 21 2013

%Y Cf. A000005, A000010, A045763, A073757, A083243-A083248, A020488.

%K nonn,less

%O 1,1

%A _Labos Elemer_, May 07 2003