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Inverse of reduced totient function.
(Formerly M2428 N0961)
6

%I M2428 N0961 #24 Dec 19 2021 10:07:03

%S 1,3,5,7,32,11,13,17,19,25,23,224,29,31,128,37,41,43,115,47,119,53,81,

%T 928,59,61,256,67,71,73,79,187,83,203,89,209,235,97,101,103,1696,107,

%U 109,121,113,295,287,127,512,131,299,137,139,319,323,149,151,157,1408

%N Inverse of reduced totient function.

%D D. H. Lehmer, Guide to Tables in the Theory of Numbers. Bulletin No. 105, National Research Council, Washington, DC, 1941, pp. 7-10.

%D N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).

%D N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

%H T. D. Noe, <a href="/A002396/b002396.txt">Table of n, a(n) for n = 1..1000</a>

%H C. Moreau, <a href="http://www.numdam.org/item?id=NAM_1898_3_17__293_0">Sur quelques théorèmes d'arithmétique</a>, Nouvelles Annales de Mathématiques, 17 (1898), 293-307.

%t max = 1000; Clear[a]; a[n_] := 100*n; a[2432] = 623104 (* given by _T. D. Noe_ *); For[m = 0; n = 1, m <= max, n = If[n == 1, 2, n + 2], For[k = n, k <= a[n], k++, If[CarmichaelLambda[k] == n, m++; Print[{n, m, k}]; a[m] = k; Break[]]]]; Table[a[n], {n, 1, max}] (* _Jean-François Alcover_, Jan 15 2015 *)

%K nonn,nice,easy

%O 1,2

%A _N. J. A. Sloane_

%E More terms from Brent Lehman (mailbjl(AT)yahoo.com), Apr 26 2005