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%I #9 Apr 13 2022 20:22:33
%S 213,323,639,713
%N Initial values providing nontrivial cyclic attractor when function defined in A085307 is iterated.
%F Algorithm: 1# factorize n; 2# arrange prime-factors by decreasing size; 3# concatenate prime factors and interpret the result as decimal number.Iterate 1#, 2#, 3#.
%e n=213 gives {213,713,3123,3473,15123,713},
%e n=323 gives {323,1917,713,3123,3473,15123,713},
%e n=639 gives {639,713,3123,3473,15123,713}.
%Y Cf. A084317-A084319, A085307, A085308, A085309.
%K base,nonn
%O 1,1
%A _Labos Elemer_, Jun 27 2003
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