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A224532 Largest number k such that phi(k) = A007374(n). 3

%I

%S 2,6,12,30,42,120,126,150,90,210,660,1242,7938,2760,1014,270,1470,810,

%T 3318,630,2370,4830,7590,1386,11220,1680,1260,5082,13890,1050,3570,

%U 33750,1890,26082,14058,2310,2730,5670,5250,70140,12690,14280,12474,3990,11850

%N Largest number k such that phi(k) = A007374(n).

%C That is, the largest number k such that phi(k) = x, with x being the least number having n solutions. - _T. D. Noe_, Apr 14 2013

%H T. D. Noe, <a href="/A224532/b224532.txt">Table of n, a(n) for n = 2..1023</a>

%H D. Bressoud, <a href="http://www.macalester.edu/~bressoud/books/CNT.m">CNT.m</a> Computational Number Theory Mathematica package.

%t Needs["CNT`"]; nn = 50; t = Table[0, {nn}]; n = 0; left = nn - 1; While[left > 0, n++; cnt = Length[PhiInverse[n]]; If[cnt <= nn && t[[cnt]] == 0, t[[cnt]] = n; left--]]; Join[{0}, Table[PhiInverse[n][[-1]], {n, Rest[t]}]]

%Y Cf. A224531.

%K nonn

%O 2,1

%A _T. D. Noe_, Apr 11 2013

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Last modified September 27 03:21 EDT 2020. Contains 337380 sequences. (Running on oeis4.)