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%I #9 Mar 01 2017 11:45:45
%S 2206,2210,2932,2950,3394,3398,3400,3402,3520,3768,3844,4240,4440,
%T 4516,4778,4782,4828,4870,4884,6428,6484,6840,7056,7624,7680,7984,
%U 8560,9072,10264
%N Terms in a specific cycle of length 29 of the map x->A098189(x).
%C Iteration of the map x -> A098189(x) enters cycles of various lengths.
%C The 29 terms in the first cycle where A098190(x)=29 are listed here in ascending order; the example section of A098190 shows them in the mapping order.
%C See other attractors in A098191-A098195.
%e The cycle follows the mapping 3768 -> 4440 -> ... -> 2210-> 3768 (returning to the first element).
%e This cycle is entered, for example, if the mapping is started at x=246 (Cf. A098190).
%t Function[s, Union@ Drop[s, #] &@ Count[DeleteDuplicates@ Map[Position[s, #] &, s], k_ /; Length@ k == 1]]@ NestList[Function[n, DivisorSum[n, # &, CoprimeQ[#, n/#] &] - EulerPhi@n], 246, 10^3] (* _Michael De Vlieger_, Mar 01 2017 *)
%o (PARI) A098189(n)=my(f=factor(n)); prod(k=1,#f~, f[k,1]^f[k,2]+1) - eulerphi(f)
%o a(n)=if(n>1, A098189(n-1), 2206) \\ _Charles R Greathouse IV_, Mar 01 2017
%Y Cf. A063919, A098189, A098190, A098191, A098193, A098194, A098195.
%K nonn,fini,full
%O 1,1
%A _Labos Elemer_, Sep 03 2004
%E Edited by _R. J. Mathar_, May 15 2009