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Numerator of new minima of phi(p-1)/(p-1), where phi is Euler's totient function and p = prime(n).
3

%I #9 Apr 14 2016 05:00:41

%S 1,1,1,4,8,16,288,256,192,768,384,3456,3072,6912,6144,55296,1658880,

%T 221184,110592,3317760,442368,13271040

%N Numerator of new minima of phi(p-1)/(p-1), where phi is Euler's totient function and p = prime(n).

%C The values of p are in A241196. The denominator is in A241198.

%e In decimal, the minima are about 1, 0.5, 0.333333, 0.266667, 0.228571, 0.207792, 0.196856, 0.195569, 0.191808, 0.185194, 0.183469, 0.181713, 0.180525, 0.173812, 0.172676, 0.171024, 0.165507, 0.165127, 0.163588.

%t tMin = {{2, 1}}; Do[p = Prime[n]; tn = EulerPhi[p - 1]/(p - 1); If[tn < tMin[[-1, -1]], AppendTo[tMin, {p, tn}]], {n, 10^7}]; Numerator[Transpose[tMin][[2]]]

%Y Cf. A008330 (phi(prime(n)-1)), A073918, A241194, A241195.

%K nonn,frac,more

%O 1,4

%A _T. D. Noe_, Apr 17 2014

%E a(20)-a(22) from _Giovanni Resta_, Apr 14 2016