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%I #9 Apr 16 2023 23:03:24
%S 17,222,111,37,1148,574,287,41,1518,759,253,23,438,219,73,5184,2592,
%T 1296,648,324,162,81,27,9,3,7,36,18,9,3,7,36,18,9,3,7,36,18,9,3,7,36,
%U 18,9,3,7,36,18,9,3,7,36,18,9,3,7,36,18,9,3,7,36,18,9,3,7,36
%N Collatz-2 (A063041) trajectory starting at 17.
%C a(23) = a(28) = 9 and a(i) = a(j) <==> i = j for i, j < 28; same cycle values as A063042 but the conjecture that this is the only cycle for all starting values is not true: see A063044
%F a(0) = 17 and a(n) = A063041(a(n-1)) for n > 0
%t NestList[If[PrimeQ[#],#*Prime[PrimePi[#]-1]+1,#/Min@@First/@FactorInteger[#]]&,17,30] (* _Jayanta Basu_, May 27 2013 *)
%Y Cf. A063041, A063042, A063044.
%K easy,nonn
%O 0,1
%A _Reinhard Zumkeller_, Jul 07 2001
%E More terms from _Sean A. Irvine_, Apr 16 2023