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%I #14 Oct 01 2015 11:49:56
%S 2,6,12,18,22,42,60,54,46,58,62,126,150,98,94,106,118,198,134,142,270,
%T 158,166,276,420,250,206,214,378,348,254,262,274,278,298,302,474,486,
%U 334,346,358,594,382,840,394,398,422,446,454,458,708,478,1050,502,1020
%N Largest solution x to phi(x) + 1 = prime(n).
%H T. D. Noe, <a href="/A066080/b066080.txt">Table of n, a(n) for n = 1..1000</a>
%H D. Bressoud, <a href="http://www.macalester.edu/~bressoud/books/CNT.m">CNT.m</a> Computational Number Theory Mathematica package.
%e For p=97: x = {97, 119, 153, 194, 195, 208, 224, 238, 260, 280, 288, 306, 312, 336, 360, 390, 420} is set of 17 solutions such that phi(x)+1=97.
%t Table[Do[s=1+EulerPhi[n]; If[Equal[s, Prime[k]], Print[{n, s}]], {n, 1, 4*Prime[k]^2}], {k, 1, 100}]
%t Needs["CNT`"]; Table[Solve[EulerPhi[x] == Prime[n] - 1, x][[-1, -1, -1]], {n, 100}] (* _T. D. Noe_, Nov 07 2011 *)
%Y Cf. A057826 (greatest number with totient 2n).
%K nonn
%O 1,1
%A _Labos Elemer_, Dec 03 2001
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