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A365368 First integer > n reached under iteration of map x -> (5/3)*round(x) when started at n, or -1 if no such integer is ever reached.

%I A365368 #4 Sep 03 2023 10:41:38
%S A365368 5,5,5,20,10245,10,20,10245,15,130,30,20,10245,105,25,45,130,30,245,
%T A365368 55,35,10245,105,40,70,120,45,130,80,50,145,245,55,95,270,60,10245,
%U A365368 105,65,520,870,70,120,2605,75,355,130,80,380,230,85,145,245,90,255,155,95
%N A365368 First integer > n reached under iteration of map x -> (5/3)*round(x) when started at n, or -1 if no such integer is ever reached.
%C A365368 Conjecture: an integer will always be reached, i.e. a(n) > 0 for all n.
%o A365368 (Python)
%o A365368 from fractions import Fraction
%o A365368 def A365368(n):
%o A365368     x = Fraction(n)
%o A365368     while x.denominator > 1 or x<=n:
%o A365368         x = Fraction(5*x.__round__(),3)
%o A365368     return int(x)
%Y A365368 Cf. A087704, A087705, A087706, A087707, A087708, A087709, A365341, A365342, A365367.
%K A365368 nonn
%O A365368 1,1
%A A365368 _Chai Wah Wu_, Sep 02 2023