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Smallest nonprime number which if used as initial term for iteration of the A000010[x] function, results in list-to-fixed-point of length=n, or 0 if no such number exists.
6

%I #8 Oct 15 2013 22:32:34

%S 1,0,4,8,15,25,51,85,187,289,685,1285,2329,4369,10537,18649,35209,

%T 66049,150289,281929,598553,1114129,2387089,4491589,8978569,16843009,

%U 36087169,71861329,143163649,286331153,579117769,1086374209,2307492233

%N Smallest nonprime number which if used as initial term for iteration of the A000010[x] function, results in list-to-fixed-point of length=n, or 0 if no such number exists.

%C Remark: length-of-iteration means the number of distinct terms to fixed point [including start and end]. While number of iterations[=required operations] equals length-1.

%C The smallest composite number is the smallest product of primes in A007755 such that the phi-iteration has exactly n terms. [From _T. D. Noe_, Sep 18 2008]

%H T. D. Noe, <a href="/A098196/b098196.txt">Table of n, a(n) for n=1..1002</a>

%e Iteration lists for the first 5 terms: {1},{0},{4,2,1},{8,4,2,1},{15,8,4,2,1},..

%Y Cf. A007755, A060611.

%K nonn

%O 1,3

%A _Labos Elemer_, Sep 13 2004

%E Corrected and extended by _T. D. Noe_, Sep 18 2008