A075108 - OEIS

A075108

First integer reached when starting with n/floor(log_2(n)) and iterating the map x -> x*ceiling(x) A075107(n) times, or -1 if no integer is ever reached.

%I #6 Oct 27 2018 22:44:51

%S 2,3,2,60,3,14,8,3,1484710602474311520,220,4,227370,560,5,4,218790,

%T 268065,570,5,1008,33,1458660,6,1925,2093,2268,7,58,60,62,2016,

%U 494764640798827359861461484,5220768,7

%N First integer reached when starting with n/floor(log_2(n)) and iterating the map x -> x*ceiling(x) A075107(n) times, or -1 if no integer is ever reached.

%e n=5: after A075107(5)=2 steps 5/floor(log_2(5)) = 5/2 -> 15/2 -> 60, therefore a(5)=60.

%Y Cf. A075103, A075121.

%K nonn

%O 2,1

%A _Reinhard Zumkeller_, Sep 02 2002